diff --git a/dom/media/MediaDataDemuxer.h b/dom/media/MediaDataDemuxer.h
index f58b3de6255b..4449d7359488 100644
--- a/dom/media/MediaDataDemuxer.h
+++ b/dom/media/MediaDataDemuxer.h
@@ -9,7 +9,7 @@
 
 #include "MediaData.h"
 #include "MediaInfo.h"
-#include "MediaPromise.h"
+#include "MozPromise.h"
 #include "TimeUnits.h"
 #include "mozilla/UniquePtr.h"
 #include "nsISupportsImpl.h"
@@ -40,7 +40,7 @@ class MediaDataDemuxer
 public:
   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaDataDemuxer)
 
-  typedef MediaPromise<nsresult, DemuxerFailureReason, /* IsExclusive = */ true> InitPromise;
+  typedef MozPromise<nsresult, DemuxerFailureReason, /* IsExclusive = */ true> InitPromise;
 
   // Initializes the demuxer. Other methods cannot be called unless
   // initialization has completed and succeeded.
@@ -133,9 +133,9 @@ public:
     uint32_t mSkipped;
   };
 
-  typedef MediaPromise<media::TimeUnit, DemuxerFailureReason, /* IsExclusive = */ true> SeekPromise;
-  typedef MediaPromise<nsRefPtr<SamplesHolder>, DemuxerFailureReason, /* IsExclusive = */ true> SamplesPromise;
-  typedef MediaPromise<uint32_t, SkipFailureHolder, /* IsExclusive = */ true> SkipAccessPointPromise;
+  typedef MozPromise<media::TimeUnit, DemuxerFailureReason, /* IsExclusive = */ true> SeekPromise;
+  typedef MozPromise<nsRefPtr<SamplesHolder>, DemuxerFailureReason, /* IsExclusive = */ true> SamplesPromise;
+  typedef MozPromise<uint32_t, SkipFailureHolder, /* IsExclusive = */ true> SkipAccessPointPromise;
 
   // Returns the TrackInfo (a.k.a Track Description) for this track.
   // The TrackInfo returned will be:
diff --git a/dom/media/MediaDecoder.cpp b/dom/media/MediaDecoder.cpp
index e70d36d73aea..c17c2f7375c4 100644
--- a/dom/media/MediaDecoder.cpp
+++ b/dom/media/MediaDecoder.cpp
@@ -121,7 +121,7 @@ public:
 StaticRefPtr<MediaMemoryTracker> MediaMemoryTracker::sUniqueInstance;
 
 PRLogModuleInfo* gStateWatchingLog;
-PRLogModuleInfo* gMediaPromiseLog;
+PRLogModuleInfo* gMozPromiseLog;
 PRLogModuleInfo* gMediaTimerLog;
 PRLogModuleInfo* gMediaSampleLog;
 
@@ -134,7 +134,7 @@ MediaDecoder::InitStatics()
 
   // Log modules.
   gMediaDecoderLog = PR_NewLogModule("MediaDecoder");
-  gMediaPromiseLog = PR_NewLogModule("MediaPromise");
+  gMozPromiseLog = PR_NewLogModule("MozPromise");
   gStateWatchingLog = PR_NewLogModule("StateWatching");
   gMediaTimerLog = PR_NewLogModule("MediaTimer");
   gMediaSampleLog = PR_NewLogModule("MediaSample");
diff --git a/dom/media/MediaDecoder.h b/dom/media/MediaDecoder.h
index 7621028476f4..8811a0a9cf68 100644
--- a/dom/media/MediaDecoder.h
+++ b/dom/media/MediaDecoder.h
@@ -189,7 +189,7 @@ destroying the MediaDecoder object.
 #include "nsIObserver.h"
 #include "nsAutoPtr.h"
 #include "nsITimer.h"
-#include "MediaPromise.h"
+#include "MozPromise.h"
 #include "MediaResource.h"
 #include "mozilla/dom/AudioChannelBinding.h"
 #include "mozilla/ReentrantMonitor.h"
@@ -274,7 +274,7 @@ public:
     MediaDecoderEventVisibility mEventVisibility;
   };
 
-  typedef MediaPromise<SeekResolveValue, bool /* aIgnored */, /* IsExclusive = */ true> SeekPromise;
+  typedef MozPromise<SeekResolveValue, bool /* aIgnored */, /* IsExclusive = */ true> SeekPromise;
 
   NS_DECL_THREADSAFE_ISUPPORTS
 
@@ -986,7 +986,7 @@ protected:
   // Returns true if heuristic dormant is supported.
   bool IsHeuristicDormantSupported() const;
 
-  MediaPromiseRequestHolder<SeekPromise> mSeekRequest;
+  MozPromiseRequestHolder<SeekPromise> mSeekRequest;
 
   // True when seeking or otherwise moving the play position around in
   // such a manner that progress event data is inaccurate. This is set
diff --git a/dom/media/MediaDecoderReader.h b/dom/media/MediaDecoderReader.h
index 2c725c220c85..5abcc6e76d1a 100644
--- a/dom/media/MediaDecoderReader.h
+++ b/dom/media/MediaDecoderReader.h
@@ -9,7 +9,7 @@
 #include "AbstractMediaDecoder.h"
 #include "MediaInfo.h"
 #include "MediaData.h"
-#include "MediaPromise.h"
+#include "MozPromise.h"
 #include "MediaQueue.h"
 #include "MediaTimer.h"
 #include "AudioCompactor.h"
@@ -66,16 +66,16 @@ public:
     CANCELED
   };
 
-  typedef MediaPromise<nsRefPtr<MetadataHolder>, ReadMetadataFailureReason, /* IsExclusive = */ true> MetadataPromise;
-  typedef MediaPromise<nsRefPtr<AudioData>, NotDecodedReason, /* IsExclusive = */ true> AudioDataPromise;
-  typedef MediaPromise<nsRefPtr<VideoData>, NotDecodedReason, /* IsExclusive = */ true> VideoDataPromise;
-  typedef MediaPromise<int64_t, nsresult, /* IsExclusive = */ true> SeekPromise;
+  typedef MozPromise<nsRefPtr<MetadataHolder>, ReadMetadataFailureReason, /* IsExclusive = */ true> MetadataPromise;
+  typedef MozPromise<nsRefPtr<AudioData>, NotDecodedReason, /* IsExclusive = */ true> AudioDataPromise;
+  typedef MozPromise<nsRefPtr<VideoData>, NotDecodedReason, /* IsExclusive = */ true> VideoDataPromise;
+  typedef MozPromise<int64_t, nsresult, /* IsExclusive = */ true> SeekPromise;
 
   // Note that, conceptually, WaitForData makes sense in a non-exclusive sense.
   // But in the current architecture it's only ever used exclusively (by MDSM),
   // so we mark it that way to verify our assumptions. If you have a use-case
   // for multiple WaitForData consumers, feel free to flip the exclusivity here.
-  typedef MediaPromise<MediaData::Type, WaitForDataRejectValue, /* IsExclusive = */ true> WaitForDataPromise;
+  typedef MozPromise<MediaData::Type, WaitForDataRejectValue, /* IsExclusive = */ true> WaitForDataPromise;
 
   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaDecoderReader)
 
@@ -386,7 +386,7 @@ protected:
   Mirror<media::NullableTimeUnit> mDuration;
 
   // State for ThrottledNotifyDataArrived.
-  MediaPromiseRequestHolder<MediaTimerPromise> mThrottledNotify;
+  MozPromiseRequestHolder<MediaTimerPromise> mThrottledNotify;
   const TimeDuration mThrottleDuration;
   TimeStamp mLastThrottledNotify;
   Maybe<media::Interval<int64_t>> mThrottledInterval;
@@ -420,8 +420,8 @@ protected:
 private:
   // Promises used only for the base-class (sync->async adapter) implementation
   // of Request{Audio,Video}Data.
-  MediaPromiseHolder<AudioDataPromise> mBaseAudioPromise;
-  MediaPromiseHolder<VideoDataPromise> mBaseVideoPromise;
+  MozPromiseHolder<AudioDataPromise> mBaseAudioPromise;
+  MozPromiseHolder<VideoDataPromise> mBaseVideoPromise;
 
   bool mTaskQueueIsBorrowed;
 
diff --git a/dom/media/MediaDecoderStateMachine.h b/dom/media/MediaDecoderStateMachine.h
index 220cc61b9d64..417a9919725a 100644
--- a/dom/media/MediaDecoderStateMachine.h
+++ b/dom/media/MediaDecoderStateMachine.h
@@ -766,7 +766,7 @@ private:
   private:
     MediaDecoderStateMachine* mSelf;
     nsRefPtr<MediaTimer> mMediaTimer;
-    MediaPromiseRequestHolder<mozilla::MediaTimerPromise> mRequest;
+    MozPromiseRequestHolder<mozilla::MediaTimerPromise> mRequest;
     TimeStamp mTarget;
 
   } mDelayedScheduler;
@@ -778,7 +778,7 @@ private:
   public:
     typedef MediaDecoderReader::AudioDataPromise AudioDataPromise;
     typedef MediaDecoderReader::VideoDataPromise VideoDataPromise;
-    typedef MediaPromise<bool, bool, /* isExclusive = */ false> HaveStartTimePromise;
+    typedef MozPromise<bool, bool, /* isExclusive = */ false> HaveStartTimePromise;
 
     NS_INLINE_DECL_THREADSAFE_REFCOUNTING(StartTimeRendezvous);
     StartTimeRendezvous(AbstractThread* aOwnerThread, bool aHasAudio, bool aHasVideo,
@@ -888,7 +888,7 @@ private:
       return aType == MediaData::AUDIO_DATA ? mAudioStartTime : mVideoStartTime;
     }
 
-    MediaPromiseHolder<HaveStartTimePromise> mHaveStartTimePromise;
+    MozPromiseHolder<HaveStartTimePromise> mHaveStartTimePromise;
     nsRefPtr<AbstractThread> mOwnerThread;
     Maybe<int64_t> mAudioStartTime;
     Maybe<int64_t> mVideoStartTime;
@@ -999,7 +999,7 @@ private:
     }
 
     SeekTarget mTarget;
-    MediaPromiseHolder<MediaDecoder::SeekPromise> mPromise;
+    MozPromiseHolder<MediaDecoder::SeekPromise> mPromise;
   };
 
   // Queued seek - moves to mPendingSeek when DecodeFirstFrame completes.
@@ -1157,8 +1157,8 @@ private:
   // Only one of a given pair of ({Audio,Video}DataPromise, WaitForDataPromise)
   // should exist at any given moment.
 
-  MediaPromiseRequestHolder<MediaDecoderReader::AudioDataPromise> mAudioDataRequest;
-  MediaPromiseRequestHolder<MediaDecoderReader::WaitForDataPromise> mAudioWaitRequest;
+  MozPromiseRequestHolder<MediaDecoderReader::AudioDataPromise> mAudioDataRequest;
+  MozPromiseRequestHolder<MediaDecoderReader::WaitForDataPromise> mAudioWaitRequest;
   const char* AudioRequestStatus()
   {
     MOZ_ASSERT(OnTaskQueue());
@@ -1171,8 +1171,8 @@ private:
     return "idle";
   }
 
-  MediaPromiseRequestHolder<MediaDecoderReader::WaitForDataPromise> mVideoWaitRequest;
-  MediaPromiseRequestHolder<MediaDecoderReader::VideoDataPromise> mVideoDataRequest;
+  MozPromiseRequestHolder<MediaDecoderReader::WaitForDataPromise> mVideoWaitRequest;
+  MozPromiseRequestHolder<MediaDecoderReader::VideoDataPromise> mVideoDataRequest;
   const char* VideoRequestStatus()
   {
     MOZ_ASSERT(OnTaskQueue());
@@ -1185,7 +1185,7 @@ private:
     return "idle";
   }
 
-  MediaPromiseRequestHolder<MediaDecoderReader::WaitForDataPromise>& WaitRequestRef(MediaData::Type aType)
+  MozPromiseRequestHolder<MediaDecoderReader::WaitForDataPromise>& WaitRequestRef(MediaData::Type aType)
   {
     MOZ_ASSERT(OnTaskQueue());
     return aType == MediaData::AUDIO_DATA ? mAudioWaitRequest : mVideoWaitRequest;
@@ -1261,7 +1261,7 @@ private:
   bool mDecodeToSeekTarget;
 
   // Track the current seek promise made by the reader.
-  MediaPromiseRequestHolder<MediaDecoderReader::SeekPromise> mSeekRequest;
+  MozPromiseRequestHolder<MediaDecoderReader::SeekPromise> mSeekRequest;
 
   // We record the playback position before we seek in order to
   // determine where the seek terminated relative to the playback position
@@ -1269,7 +1269,7 @@ private:
   int64_t mCurrentTimeBeforeSeek;
 
   // Track our request for metadata from the reader.
-  MediaPromiseRequestHolder<MediaDecoderReader::MetadataPromise> mMetadataRequest;
+  MozPromiseRequestHolder<MediaDecoderReader::MetadataPromise> mMetadataRequest;
 
   // Stores presentation info required for playback. The decoder monitor
   // must be held when accessing this.
diff --git a/dom/media/MediaFormatReader.h b/dom/media/MediaFormatReader.h
index 3aba953f2230..134af24ec422 100644
--- a/dom/media/MediaFormatReader.h
+++ b/dom/media/MediaFormatReader.h
@@ -227,12 +227,12 @@ private:
     bool mDiscontinuity;
 
     // Pending seek.
-    MediaPromiseRequestHolder<MediaTrackDemuxer::SeekPromise> mSeekRequest;
+    MozPromiseRequestHolder<MediaTrackDemuxer::SeekPromise> mSeekRequest;
 
     // Queued demux samples waiting to be decoded.
     nsTArray<nsRefPtr<MediaRawData>> mQueuedSamples;
-    MediaPromiseRequestHolder<MediaTrackDemuxer::SamplesPromise> mDemuxRequest;
-    MediaPromiseHolder<WaitForDataPromise> mWaitingPromise;
+    MozPromiseRequestHolder<MediaTrackDemuxer::SamplesPromise> mDemuxRequest;
+    MozPromiseHolder<WaitForDataPromise> mWaitingPromise;
     bool HasWaitingPromise()
     {
       MOZ_ASSERT(mOwner->OnTaskQueue());
@@ -308,7 +308,7 @@ private:
       DecoderData(aOwner, aType, aDecodeAhead)
     {}
 
-    MediaPromiseHolder<PromiseType> mPromise;
+    MozPromiseHolder<PromiseType> mPromise;
 
     bool HasPromise() override
     {
@@ -335,7 +335,7 @@ private:
   // Demuxer objects.
   void OnDemuxerInitDone(nsresult);
   void OnDemuxerInitFailed(DemuxerFailureReason aFailure);
-  MediaPromiseRequestHolder<MediaDataDemuxer::InitPromise> mDemuxerInitRequest;
+  MozPromiseRequestHolder<MediaDataDemuxer::InitPromise> mDemuxerInitRequest;
   void OnDemuxFailed(TrackType aTrack, DemuxerFailureReason aFailure);
 
   void DoDemuxVideo();
@@ -353,7 +353,7 @@ private:
   }
 
   void SkipVideoDemuxToNextKeyFrame(media::TimeUnit aTimeThreshold);
-  MediaPromiseRequestHolder<MediaTrackDemuxer::SkipAccessPointPromise> mSkipRequest;
+  MozPromiseRequestHolder<MediaTrackDemuxer::SkipAccessPointPromise> mSkipRequest;
   void OnVideoSkipCompleted(uint32_t aSkipped);
   void OnVideoSkipFailed(MediaTrackDemuxer::SkipFailureHolder aFailure);
 
@@ -368,7 +368,7 @@ private:
   // Metadata objects
   // True if we've read the streams' metadata.
   bool mInitDone;
-  MediaPromiseHolder<MetadataPromise> mMetadataPromise;
+  MozPromiseHolder<MetadataPromise> mMetadataPromise;
   // Accessed from multiple thread, in particular the MediaDecoderStateMachine,
   // however the value doesn't change after reading the metadata.
   bool mSeekable;
@@ -404,7 +404,7 @@ private:
   }
   // Temporary seek information while we wait for the data
   Maybe<media::TimeUnit> mPendingSeekTime;
-  MediaPromiseHolder<SeekPromise> mSeekPromise;
+  MozPromiseHolder<SeekPromise> mSeekPromise;
 
 #ifdef MOZ_EME
   nsRefPtr<CDMProxy> mCDMProxy;
diff --git a/dom/media/MediaTaskQueue.h b/dom/media/MediaTaskQueue.h
index 25a641e92c4b..5371d5ff9211 100644
--- a/dom/media/MediaTaskQueue.h
+++ b/dom/media/MediaTaskQueue.h
@@ -13,7 +13,7 @@
 #include "mozilla/unused.h"
 #include "SharedThreadPool.h"
 #include "nsThreadUtils.h"
-#include "MediaPromise.h"
+#include "MozPromise.h"
 #include "TaskDispatcher.h"
 
 class nsIRunnable;
@@ -22,7 +22,7 @@ namespace mozilla {
 
 class SharedThreadPool;
 
-typedef MediaPromise<bool, bool, false> ShutdownPromise;
+typedef MozPromise<bool, bool, false> ShutdownPromise;
 
 // Abstracts executing runnables in order in a thread pool. The runnables
 // dispatched to the MediaTaskQueue will be executed in the order in which
@@ -156,7 +156,7 @@ protected:
 
   // True if we've started our shutdown process.
   bool mIsShutdown;
-  MediaPromiseHolder<ShutdownPromise> mShutdownPromise;
+  MozPromiseHolder<ShutdownPromise> mShutdownPromise;
 
   // True if we're flushing; we reject new tasks if we're flushing.
   bool mIsFlushing;
diff --git a/dom/media/MediaTimer.h b/dom/media/MediaTimer.h
index 302320f1d04b..117a5e52088d 100644
--- a/dom/media/MediaTimer.h
+++ b/dom/media/MediaTimer.h
@@ -7,7 +7,7 @@
 #if !defined(MediaTimer_h_)
 #define MediaTimer_h_
 
-#include "MediaPromise.h"
+#include "MozPromise.h"
 
 #include <queue>
 
@@ -28,11 +28,11 @@ extern PRLogModuleInfo* gMediaTimerLog;
 
 // This promise type is only exclusive because so far there isn't a reason for
 // it not to be. Feel free to change that.
-typedef MediaPromise<bool, bool, /* IsExclusive = */ true> MediaTimerPromise;
+typedef MozPromise<bool, bool, /* IsExclusive = */ true> MediaTimerPromise;
 
 // Timers only know how to fire at a given thread, which creates an impedence
 // mismatch with code that operates with MediaTaskQueues. This class solves
-// that mismatch with a dedicated (but shared) thread and a nice MediaPromise-y
+// that mismatch with a dedicated (but shared) thread and a nice MozPromise-y
 // interface.
 class MediaTimer
 {
diff --git a/dom/media/MediaPromise.h b/dom/media/MozPromise.h
similarity index 86%
rename from dom/media/MediaPromise.h
rename to dom/media/MozPromise.h
index 5eff7d589730..86fcfb030008 100644
--- a/dom/media/MediaPromise.h
+++ b/dom/media/MozPromise.h
@@ -4,8 +4,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#if !defined(MediaPromise_h_)
-#define MediaPromise_h_
+#if !defined(MozPromise_h_)
+#define MozPromise_h_
 
 #include "mozilla/Logging.h"
 
@@ -20,18 +20,18 @@
 #include "mozilla/Monitor.h"
 #include "mozilla/unused.h"
 
-/* Polyfill __func__ on MSVC for consumers to pass to the MediaPromise API. */
+/* Polyfill __func__ on MSVC for consumers to pass to the MozPromise API. */
 #ifdef _MSC_VER
 #define __func__ __FUNCTION__
 #endif
 
 namespace mozilla {
 
-extern PRLogModuleInfo* gMediaPromiseLog;
+extern PRLogModuleInfo* gMozPromiseLog;
 
 #define PROMISE_LOG(x, ...) \
-  MOZ_ASSERT(gMediaPromiseLog); \
-  MOZ_LOG(gMediaPromiseLog, mozilla::LogLevel::Debug, (x, ##__VA_ARGS__))
+  MOZ_ASSERT(gMozPromiseLog); \
+  MOZ_LOG(gMozPromiseLog, mozilla::LogLevel::Debug, (x, ##__VA_ARGS__))
 
 namespace detail {
 template<typename ThisType, typename Ret, typename ArgType>
@@ -75,14 +75,14 @@ struct ReturnTypeIs {
  * callbacks to be invoked (asynchronously, on a specified thread) when the
  * request is either completed (resolved) or cannot be completed (rejected).
  *
- * MediaPromises attempt to mirror the spirit of JS Promises to the extent that
- * is possible (and desirable) in C++. While the intent is that MediaPromises
+ * MozPromises attempt to mirror the spirit of JS Promises to the extent that
+ * is possible (and desirable) in C++. While the intent is that MozPromises
  * feel familiar to programmers who are accustomed to their JS-implemented cousin,
  * we don't shy away from imposing restrictions and adding features that make
  * sense for the use cases we encounter.
  *
- * A MediaPromise is ThreadSafe, and may be ->Then()ed on any thread. The Then()
- * call accepts resolve and reject callbacks, and returns a MediaPromise::Request.
+ * A MozPromise is ThreadSafe, and may be ->Then()ed on any thread. The Then()
+ * call accepts resolve and reject callbacks, and returns a MozPromise::Request.
  * The Request object serves several purposes for the consumer.
  *
  *   (1) It allows the caller to cancel the delivery of the resolve/reject value
@@ -91,33 +91,33 @@ struct ReturnTypeIs {
  *
  *   (2) It provides access to a "Completion Promise", which is roughly analagous
  *       to the Promise returned directly by ->then() calls on JS promises. If
- *       the resolve/reject callback returns a new MediaPromise, that promise is
+ *       the resolve/reject callback returns a new MozPromise, that promise is
  *       chained to the completion promise, such that its resolve/reject value
  *       will be forwarded along when it arrives. If the resolve/reject callback
  *       returns void, the completion promise is resolved/rejected with the same
  *       value that was passed to the callback.
  *
- * The MediaPromise APIs skirt traditional XPCOM convention by returning nsRefPtrs
+ * The MozPromise APIs skirt traditional XPCOM convention by returning nsRefPtrs
  * (rather than already_AddRefed) from various methods. This is done to allow elegant
  * chaining of calls without cluttering up the code with intermediate variables, and
  * without introducing separate API variants for callers that want a return value
  * (from, say, ->Then()) from those that don't.
  *
- * When IsExclusive is true, the MediaPromise does a release-mode assertion that
+ * When IsExclusive is true, the MozPromise does a release-mode assertion that
  * there is at most one call to either Then(...) or ChainTo(...).
  */
 
-class MediaPromiseRefcountable
+class MozPromiseRefcountable
 {
 public:
-  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaPromiseRefcountable)
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MozPromiseRefcountable)
 protected:
-  virtual ~MediaPromiseRefcountable() {}
+  virtual ~MozPromiseRefcountable() {}
 };
 
-template<typename T> class MediaPromiseHolder;
+template<typename T> class MozPromiseHolder;
 template<typename ResolveValueT, typename RejectValueT, bool IsExclusive>
-class MediaPromise : public MediaPromiseRefcountable
+class MozPromise : public MozPromiseRefcountable
 {
 public:
   typedef ResolveValueT ResolveValueType;
@@ -168,47 +168,47 @@ public:
   };
 
 protected:
-  // MediaPromise is the public type, and never constructed directly. Construct
-  // a MediaPromise::Private, defined below.
-  explicit MediaPromise(const char* aCreationSite)
+  // MozPromise is the public type, and never constructed directly. Construct
+  // a MozPromise::Private, defined below.
+  explicit MozPromise(const char* aCreationSite)
     : mCreationSite(aCreationSite)
-    , mMutex("MediaPromise Mutex")
+    , mMutex("MozPromise Mutex")
     , mHaveRequest(false)
   {
-    PROMISE_LOG("%s creating MediaPromise (%p)", mCreationSite, this);
+    PROMISE_LOG("%s creating MozPromise (%p)", mCreationSite, this);
   }
 
 public:
-  // MediaPromise::Private allows us to separate the public interface (upon which
+  // MozPromise::Private allows us to separate the public interface (upon which
   // consumers of the promise may invoke methods like Then()) from the private
   // interface (upon which the creator of the promise may invoke Resolve() or
-  // Reject()). APIs should create and store a MediaPromise::Private (usually
-  // via a MediaPromiseHolder), and return a MediaPromise to consumers.
+  // Reject()). APIs should create and store a MozPromise::Private (usually
+  // via a MozPromiseHolder), and return a MozPromise to consumers.
   //
   // NB: We can include the definition of this class inline once B2G ICS is gone.
   class Private;
 
   template<typename ResolveValueType_>
-  static nsRefPtr<MediaPromise>
+  static nsRefPtr<MozPromise>
   CreateAndResolve(ResolveValueType_&& aResolveValue, const char* aResolveSite)
   {
-    nsRefPtr<typename MediaPromise::Private> p = new MediaPromise::Private(aResolveSite);
+    nsRefPtr<typename MozPromise::Private> p = new MozPromise::Private(aResolveSite);
     p->Resolve(Forward<ResolveValueType_>(aResolveValue), aResolveSite);
     return p.forget();
   }
 
   template<typename RejectValueType_>
-  static nsRefPtr<MediaPromise>
+  static nsRefPtr<MozPromise>
   CreateAndReject(RejectValueType_&& aRejectValue, const char* aRejectSite)
   {
-    nsRefPtr<typename MediaPromise::Private> p = new MediaPromise::Private(aRejectSite);
+    nsRefPtr<typename MozPromise::Private> p = new MozPromise::Private(aRejectSite);
     p->Reject(Forward<RejectValueType_>(aRejectValue), aRejectSite);
     return p.forget();
   }
 
-  typedef MediaPromise<nsTArray<ResolveValueType>, RejectValueType, IsExclusive> AllPromiseType;
+  typedef MozPromise<nsTArray<ResolveValueType>, RejectValueType, IsExclusive> AllPromiseType;
 private:
-  class AllPromiseHolder : public MediaPromiseRefcountable
+  class AllPromiseHolder : public MozPromiseRefcountable
   {
   public:
     explicit AllPromiseHolder(size_t aDependentPromises)
@@ -255,7 +255,7 @@ private:
   };
 public:
 
-  static nsRefPtr<AllPromiseType> All(AbstractThread* aProcessingThread, nsTArray<nsRefPtr<MediaPromise>>& aPromises)
+  static nsRefPtr<AllPromiseType> All(AbstractThread* aProcessingThread, nsTArray<nsRefPtr<MozPromise>>& aPromises)
   {
     nsRefPtr<AllPromiseHolder> holder = new AllPromiseHolder(aPromises.Length());
     for (size_t i = 0; i < aPromises.Length(); ++i) {
@@ -267,7 +267,7 @@ public:
     return holder->Promise();
   }
 
-  class Request : public MediaPromiseRefcountable
+  class Request : public MozPromiseRefcountable
   {
   public:
     virtual void Disconnect() = 0;
@@ -276,7 +276,7 @@ public:
     // tries to access an inherited protected member.
     bool IsDisconnected() const { return mDisconnected; }
 
-    virtual MediaPromise* CompletionPromise() = 0;
+    virtual MozPromise* CompletionPromise() = 0;
 
   protected:
     Request() : mComplete(false), mDisconnected(false) {}
@@ -300,7 +300,7 @@ protected:
     class ResolveOrRejectRunnable : public nsRunnable
     {
     public:
-      ResolveOrRejectRunnable(ThenValueBase* aThenValue, MediaPromise* aPromise)
+      ResolveOrRejectRunnable(ThenValueBase* aThenValue, MozPromise* aPromise)
         : mThenValue(aThenValue)
         , mPromise(aPromise)
       {
@@ -323,23 +323,23 @@ protected:
 
     private:
       nsRefPtr<ThenValueBase> mThenValue;
-      nsRefPtr<MediaPromise> mPromise;
+      nsRefPtr<MozPromise> mPromise;
     };
 
     explicit ThenValueBase(AbstractThread* aResponseTarget, const char* aCallSite)
       : mResponseTarget(aResponseTarget), mCallSite(aCallSite) {}
 
-    MediaPromise* CompletionPromise() override
+    MozPromise* CompletionPromise() override
     {
       MOZ_DIAGNOSTIC_ASSERT(mResponseTarget->IsCurrentThreadIn());
       MOZ_DIAGNOSTIC_ASSERT(!Request::mComplete);
       if (!mCompletionPromise) {
-        mCompletionPromise = new MediaPromise::Private("<completion promise>");
+        mCompletionPromise = new MozPromise::Private("<completion promise>");
       }
       return mCompletionPromise;
     }
 
-    void Dispatch(MediaPromise *aPromise)
+    void Dispatch(MozPromise *aPromise)
     {
       aPromise->mMutex.AssertCurrentThreadOwns();
       MOZ_ASSERT(!aPromise->IsPending());
@@ -371,7 +371,7 @@ protected:
     }
 
   protected:
-    virtual already_AddRefed<MediaPromise> DoResolveOrRejectInternal(const ResolveOrRejectValue& aValue) = 0;
+    virtual already_AddRefed<MozPromise> DoResolveOrRejectInternal(const ResolveOrRejectValue& aValue) = 0;
 
     void DoResolveOrReject(const ResolveOrRejectValue& aValue)
     {
@@ -382,16 +382,16 @@ protected:
       }
 
       // Invoke the resolve or reject method.
-      nsRefPtr<MediaPromise> p = DoResolveOrRejectInternal(aValue);
+      nsRefPtr<MozPromise> p = DoResolveOrRejectInternal(aValue);
 
       // If there's a completion promise, resolve it appropriately with the
       // result of the method.
       //
-      // We jump through some hoops to cast to MediaPromise::Private here. This
+      // We jump through some hoops to cast to MozPromise::Private here. This
       // can go away when we can just declare mCompletionPromise as
-      // MediaPromise::Private. See the declaration below.
-      nsRefPtr<MediaPromise::Private> completionPromise =
-        dont_AddRef(static_cast<MediaPromise::Private*>(mCompletionPromise.forget().take()));
+      // MozPromise::Private. See the declaration below.
+      nsRefPtr<MozPromise::Private> completionPromise =
+        dont_AddRef(static_cast<MozPromise::Private*>(mCompletionPromise.forget().take()));
       if (completionPromise) {
         if (p) {
           p->ChainTo(completionPromise.forget(), "<chained completion promise>");
@@ -403,11 +403,11 @@ protected:
 
     nsRefPtr<AbstractThread> mResponseTarget; // May be released on any thread.
 
-    // Declaring nsRefPtr<MediaPromise::Private> here causes build failures
-    // on MSVC because MediaPromise::Private is only forward-declared at this
-    // point. This hack can go away when we inline-declare MediaPromise::Private,
+    // Declaring nsRefPtr<MozPromise::Private> here causes build failures
+    // on MSVC because MozPromise::Private is only forward-declared at this
+    // point. This hack can go away when we inline-declare MozPromise::Private,
     // which is blocked on the B2G ICS compiler being too old.
-    nsRefPtr<MediaPromise> mCompletionPromise;
+    nsRefPtr<MozPromise> mCompletionPromise;
 
     const char* mCallSite;
   };
@@ -418,9 +418,9 @@ protected:
    */
 
   template<typename ThisType, typename MethodType, typename ValueType>
-  static typename EnableIf<ReturnTypeIs<MethodType, nsRefPtr<MediaPromise>>::value &&
+  static typename EnableIf<ReturnTypeIs<MethodType, nsRefPtr<MozPromise>>::value &&
                            TakesArgument<MethodType>::value,
-                           already_AddRefed<MediaPromise>>::Type
+                           already_AddRefed<MozPromise>>::Type
   InvokeCallbackMethod(ThisType* aThisVal, MethodType aMethod, ValueType&& aValue)
   {
     return ((*aThisVal).*aMethod)(Forward<ValueType>(aValue)).forget();
@@ -429,7 +429,7 @@ protected:
   template<typename ThisType, typename MethodType, typename ValueType>
   static typename EnableIf<ReturnTypeIs<MethodType, void>::value &&
                            TakesArgument<MethodType>::value,
-                           already_AddRefed<MediaPromise>>::Type
+                           already_AddRefed<MozPromise>>::Type
   InvokeCallbackMethod(ThisType* aThisVal, MethodType aMethod, ValueType&& aValue)
   {
     ((*aThisVal).*aMethod)(Forward<ValueType>(aValue));
@@ -437,9 +437,9 @@ protected:
   }
 
   template<typename ThisType, typename MethodType, typename ValueType>
-  static typename EnableIf<ReturnTypeIs<MethodType, nsRefPtr<MediaPromise>>::value &&
+  static typename EnableIf<ReturnTypeIs<MethodType, nsRefPtr<MozPromise>>::value &&
                            !TakesArgument<MethodType>::value,
-                           already_AddRefed<MediaPromise>>::Type
+                           already_AddRefed<MozPromise>>::Type
   InvokeCallbackMethod(ThisType* aThisVal, MethodType aMethod, ValueType&& aValue)
   {
     return ((*aThisVal).*aMethod)().forget();
@@ -448,7 +448,7 @@ protected:
   template<typename ThisType, typename MethodType, typename ValueType>
   static typename EnableIf<ReturnTypeIs<MethodType, void>::value &&
                            !TakesArgument<MethodType>::value,
-                           already_AddRefed<MediaPromise>>::Type
+                           already_AddRefed<MozPromise>>::Type
   InvokeCallbackMethod(ThisType* aThisVal, MethodType aMethod, ValueType&& aValue)
   {
     ((*aThisVal).*aMethod)();
@@ -478,9 +478,9 @@ protected:
   }
 
   protected:
-    virtual already_AddRefed<MediaPromise> DoResolveOrRejectInternal(const ResolveOrRejectValue& aValue) override
+    virtual already_AddRefed<MozPromise> DoResolveOrRejectInternal(const ResolveOrRejectValue& aValue) override
     {
-      nsRefPtr<MediaPromise> completion;
+      nsRefPtr<MozPromise> completion;
       if (aValue.IsResolve()) {
         completion = InvokeCallbackMethod(mThisVal.get(), mResolveMethod, aValue.ResolveValue());
       } else {
@@ -530,14 +530,14 @@ protected:
   }
 
   protected:
-    virtual already_AddRefed<MediaPromise> DoResolveOrRejectInternal(const ResolveOrRejectValue& aValue) override
+    virtual already_AddRefed<MozPromise> DoResolveOrRejectInternal(const ResolveOrRejectValue& aValue) override
     {
       // Note: The usage of InvokeCallbackMethod here requires that
       // ResolveFunction/RejectFunction are capture-lambdas (i.e. anonymous
       // classes with ::operator()), since it allows us to share code more easily.
       // We could fix this if need be, though it's quite easy to work around by
       // just capturing something.
-      nsRefPtr<MediaPromise> completion;
+      nsRefPtr<MozPromise> completion;
       if (aValue.IsResolve()) {
         completion = InvokeCallbackMethod(mResolveFunction.ptr(), &ResolveFunction::operator(), aValue.ResolveValue());
       } else {
@@ -647,9 +647,9 @@ protected:
     }
   }
 
-  virtual ~MediaPromise()
+  virtual ~MozPromise()
   {
-    PROMISE_LOG("MediaPromise::~MediaPromise [this=%p]", this);
+    PROMISE_LOG("MozPromise::~MozPromise [this=%p]", this);
     MOZ_ASSERT(!IsPending());
     MOZ_ASSERT(mThenValues.IsEmpty());
     MOZ_ASSERT(mChainedPromises.IsEmpty());
@@ -664,18 +664,18 @@ protected:
 };
 
 template<typename ResolveValueT, typename RejectValueT, bool IsExclusive>
-class MediaPromise<ResolveValueT, RejectValueT, IsExclusive>::Private
-  : public MediaPromise<ResolveValueT, RejectValueT, IsExclusive>
+class MozPromise<ResolveValueT, RejectValueT, IsExclusive>::Private
+  : public MozPromise<ResolveValueT, RejectValueT, IsExclusive>
 {
 public:
-  explicit Private(const char* aCreationSite) : MediaPromise(aCreationSite) {}
+  explicit Private(const char* aCreationSite) : MozPromise(aCreationSite) {}
 
   template<typename ResolveValueT_>
   void Resolve(ResolveValueT_&& aResolveValue, const char* aResolveSite)
   {
     MutexAutoLock lock(mMutex);
     MOZ_ASSERT(IsPending());
-    PROMISE_LOG("%s resolving MediaPromise (%p created at %s)", aResolveSite, this, mCreationSite);
+    PROMISE_LOG("%s resolving MozPromise (%p created at %s)", aResolveSite, this, mCreationSite);
     mValue.SetResolve(Forward<ResolveValueT_>(aResolveValue));
     DispatchAll();
   }
@@ -685,7 +685,7 @@ public:
   {
     MutexAutoLock lock(mMutex);
     MOZ_ASSERT(IsPending());
-    PROMISE_LOG("%s rejecting MediaPromise (%p created at %s)", aRejectSite, this, mCreationSite);
+    PROMISE_LOG("%s rejecting MozPromise (%p created at %s)", aRejectSite, this, mCreationSite);
     mValue.SetReject(Forward<RejectValueT_>(aRejectValue));
     DispatchAll();
   }
@@ -695,28 +695,28 @@ public:
   {
     MutexAutoLock lock(mMutex);
     MOZ_ASSERT(IsPending());
-    PROMISE_LOG("%s resolveOrRejecting MediaPromise (%p created at %s)", aSite, this, mCreationSite);
+    PROMISE_LOG("%s resolveOrRejecting MozPromise (%p created at %s)", aSite, this, mCreationSite);
     mValue = Forward<ResolveOrRejectValue_>(aValue);
     DispatchAll();
   }
 };
 
 // A generic promise type that does the trick for simple use cases.
-typedef MediaPromise<bool, nsresult, /* IsExclusive = */ false> GenericPromise;
+typedef MozPromise<bool, nsresult, /* IsExclusive = */ false> GenericPromise;
 
 /*
  * Class to encapsulate a promise for a particular role. Use this as the member
  * variable for a class whose method returns a promise.
  */
 template<typename PromiseType>
-class MediaPromiseHolder
+class MozPromiseHolder
 {
 public:
-  MediaPromiseHolder()
+  MozPromiseHolder()
     : mMonitor(nullptr) {}
 
   // Move semantics.
-  MediaPromiseHolder& operator=(MediaPromiseHolder&& aOther)
+  MozPromiseHolder& operator=(MozPromiseHolder&& aOther)
   {
     MOZ_ASSERT(!mMonitor && !aOther.mMonitor);
     MOZ_DIAGNOSTIC_ASSERT(!mPromise);
@@ -725,7 +725,7 @@ public:
     return *this;
   }
 
-  ~MediaPromiseHolder() { MOZ_ASSERT(!mPromise); }
+  ~MozPromiseHolder() { MOZ_ASSERT(!mPromise); }
 
   already_AddRefed<PromiseType> Ensure(const char* aMethodName) {
     if (mMonitor) {
@@ -806,15 +806,15 @@ private:
 };
 
 /*
- * Class to encapsulate a MediaPromise::Request reference. Use this as the member
- * variable for a class waiting on a media promise.
+ * Class to encapsulate a MozPromise::Request reference. Use this as the member
+ * variable for a class waiting on a MozPromise.
  */
 template<typename PromiseType>
-class MediaPromiseRequestHolder
+class MozPromiseRequestHolder
 {
 public:
-  MediaPromiseRequestHolder() {}
-  ~MediaPromiseRequestHolder() { MOZ_ASSERT(!mRequest); }
+  MozPromiseRequestHolder() {}
+  ~MozPromiseRequestHolder() { MOZ_ASSERT(!mRequest); }
 
   void Begin(typename PromiseType::Request* aRequest)
   {
diff --git a/dom/media/StateMirroring.h b/dom/media/StateMirroring.h
index 7929958492c3..c9a51c0716d1 100644
--- a/dom/media/StateMirroring.h
+++ b/dom/media/StateMirroring.h
@@ -7,7 +7,7 @@
 #if !defined(StateMirroring_h_)
 #define StateMirroring_h_
 
-#include "MediaPromise.h"
+#include "MozPromise.h"
 
 #include "StateWatching.h"
 #include "TaskDispatcher.h"
diff --git a/dom/media/VideoUtils.h b/dom/media/VideoUtils.h
index e810989bcb55..e2274302ed5b 100644
--- a/dom/media/VideoUtils.h
+++ b/dom/media/VideoUtils.h
@@ -13,7 +13,7 @@
 #include "nsIThread.h"
 #include "nsSize.h"
 #include "nsRect.h"
-#include "MediaPromise.h"
+#include "MozPromise.h"
 
 #if !(defined(XP_WIN) || defined(XP_MACOSX) || defined(LINUX)) || \
     defined(MOZ_ASAN)
@@ -215,7 +215,7 @@ class SharedThreadPool;
 // wait on tasks in the PLAYBACK thread pool.
 //
 // No new dependencies on this mechanism should be added, as methods are being
-// made async supported by MediaPromise, making this unnecessary and
+// made async supported by MozPromise, making this unnecessary and
 // permitting unifying the pool.
 enum class MediaThreadType {
   PLAYBACK, // MediaDecoderStateMachine and MediaDecoderReader
diff --git a/dom/media/android/AndroidMediaReader.h b/dom/media/android/AndroidMediaReader.h
index 408fa04bbd5b..3d3c8591edad 100644
--- a/dom/media/android/AndroidMediaReader.h
+++ b/dom/media/android/AndroidMediaReader.h
@@ -36,8 +36,8 @@ class AndroidMediaReader : public MediaDecoderReader
   int64_t mVideoSeekTimeUs;
   int64_t mAudioSeekTimeUs;
   nsRefPtr<VideoData> mLastVideoFrame;
-  MediaPromiseHolder<MediaDecoderReader::SeekPromise> mSeekPromise;
-  MediaPromiseRequestHolder<MediaDecoderReader::VideoDataPromise> mSeekRequest;
+  MozPromiseHolder<MediaDecoderReader::SeekPromise> mSeekPromise;
+  MozPromiseRequestHolder<MediaDecoderReader::VideoDataPromise> mSeekRequest;
 public:
   AndroidMediaReader(AbstractMediaDecoder* aDecoder,
                      const nsACString& aContentType);
diff --git a/dom/media/eme/CDMProxy.h b/dom/media/eme/CDMProxy.h
index e05640e2c38e..e76a1df040e3 100644
--- a/dom/media/eme/CDMProxy.h
+++ b/dom/media/eme/CDMProxy.h
@@ -14,7 +14,7 @@
 #include "nsIThread.h"
 #include "GMPDecryptorProxy.h"
 #include "mozilla/CDMCaps.h"
-#include "MediaPromise.h"
+#include "MozPromise.h"
 
 namespace mozilla {
 class MediaRawData;
@@ -44,7 +44,7 @@ public:
 
   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(CDMProxy)
 
-  typedef MediaPromise<DecryptResult, DecryptResult, /* IsExclusive = */ true> DecryptPromise;
+  typedef MozPromise<DecryptResult, DecryptResult, /* IsExclusive = */ true> DecryptPromise;
 
   // Main thread only.
   CDMProxy(dom::MediaKeys* aKeys, const nsAString& aKeySystem);
@@ -259,7 +259,7 @@ private:
     nsRefPtr<MediaRawData> mSample;
   private:
     ~DecryptJob() {}
-    MediaPromiseHolder<DecryptPromise> mPromise;
+    MozPromiseHolder<DecryptPromise> mPromise;
   };
   // GMP thread only.
   void gmp_Decrypt(nsRefPtr<DecryptJob> aJob);
diff --git a/dom/media/fmp4/MP4Reader.h b/dom/media/fmp4/MP4Reader.h
index 86af7729ba8d..32d1617a8028 100644
--- a/dom/media/fmp4/MP4Reader.h
+++ b/dom/media/fmp4/MP4Reader.h
@@ -224,7 +224,7 @@ private:
       mPromise.SetMonitor(&mMonitor);
     }
 
-    MediaPromiseHolder<PromiseType> mPromise;
+    MozPromiseHolder<PromiseType> mPromise;
 
     bool HasPromise() override { return !mPromise.IsEmpty(); }
     void RejectPromise(MediaDecoderReader::NotDecodedReason aReason,
diff --git a/dom/media/gtest/TestMediaPromise.cpp b/dom/media/gtest/TestMozPromise.cpp
similarity index 95%
rename from dom/media/gtest/TestMediaPromise.cpp
rename to dom/media/gtest/TestMozPromise.cpp
index 265bb7a9468f..530391c0f872 100644
--- a/dom/media/gtest/TestMediaPromise.cpp
+++ b/dom/media/gtest/TestMozPromise.cpp
@@ -6,13 +6,13 @@
 #include "gtest/gtest.h"
 #include "nsISupportsImpl.h"
 #include "MediaTaskQueue.h"
-#include "MediaPromise.h"
+#include "MozPromise.h"
 #include "SharedThreadPool.h"
 #include "VideoUtils.h"
 
 using namespace mozilla;
 
-typedef MediaPromise<int, double, false> TestPromise;
+typedef MozPromise<int, double, false> TestPromise;
 typedef TestPromise::ResolveOrRejectValue RRValue;
 
 class MOZ_STACK_CLASS AutoTaskQueue
@@ -88,7 +88,7 @@ RunOnTaskQueue(MediaTaskQueue* aQueue, FunctionType aFun)
 // std::function can't come soon enough. :-(
 #define DO_FAIL []()->void { EXPECT_TRUE(false); }
 
-TEST(MediaPromise, BasicResolve)
+TEST(MozPromise, BasicResolve)
 {
   AutoTaskQueue atq;
   nsRefPtr<MediaTaskQueue> queue = atq.TaskQueue();
@@ -99,7 +99,7 @@ TEST(MediaPromise, BasicResolve)
   });
 }
 
-TEST(MediaPromise, BasicReject)
+TEST(MozPromise, BasicReject)
 {
   AutoTaskQueue atq;
   nsRefPtr<MediaTaskQueue> queue = atq.TaskQueue();
@@ -110,7 +110,7 @@ TEST(MediaPromise, BasicReject)
   });
 }
 
-TEST(MediaPromise, AsyncResolve)
+TEST(MozPromise, AsyncResolve)
 {
   AutoTaskQueue atq;
   nsRefPtr<MediaTaskQueue> queue = atq.TaskQueue();
@@ -139,7 +139,7 @@ TEST(MediaPromise, AsyncResolve)
   });
 }
 
-TEST(MediaPromise, CompletionPromises)
+TEST(MozPromise, CompletionPromises)
 {
   bool invokedPass = false;
   AutoTaskQueue atq;
@@ -171,7 +171,7 @@ TEST(MediaPromise, CompletionPromises)
   });
 }
 
-TEST(MediaPromise, PromiseAllResolve)
+TEST(MozPromise, PromiseAllResolve)
 {
   AutoTaskQueue atq;
   nsRefPtr<MediaTaskQueue> queue = atq.TaskQueue();
@@ -195,7 +195,7 @@ TEST(MediaPromise, PromiseAllResolve)
   });
 }
 
-TEST(MediaPromise, PromiseAllReject)
+TEST(MozPromise, PromiseAllReject)
 {
   AutoTaskQueue atq;
   nsRefPtr<MediaTaskQueue> queue = atq.TaskQueue();
diff --git a/dom/media/gtest/moz.build b/dom/media/gtest/moz.build
index 551a3430e89f..2e8db6947801 100644
--- a/dom/media/gtest/moz.build
+++ b/dom/media/gtest/moz.build
@@ -10,7 +10,7 @@ UNIFIED_SOURCES += [
     'TestGMPCrossOrigin.cpp',
     'TestGMPRemoveAndDelete.cpp',
     'TestIntervalSet.cpp',
-    'TestMediaPromise.cpp',
+    'TestMozPromise.cpp',
     'TestMP3Demuxer.cpp',
     'TestMP4Demuxer.cpp',
     # 'TestMP4Reader.cpp', disabled so we can turn check tests back on (bug 1175752)
diff --git a/dom/media/mediasource/MediaSourceReader.h b/dom/media/mediasource/MediaSourceReader.h
index 500290764385..bc5e82d42983 100644
--- a/dom/media/mediasource/MediaSourceReader.h
+++ b/dom/media/mediasource/MediaSourceReader.h
@@ -206,7 +206,7 @@ private:
   int64_t GetReaderAudioTime(int64_t aTime) const;
   int64_t GetReaderVideoTime(int64_t aTime) const;
 
-  // Will reject the MediaPromise with END_OF_STREAM if mediasource has ended
+  // Will reject the MozPromise with END_OF_STREAM if mediasource has ended
   // or with WAIT_FOR_DATA otherwise.
   void CheckForWaitOrEndOfStream(MediaData::Type aType, int64_t aTime /* microseconds */);
 
@@ -234,15 +234,15 @@ private:
   nsRefPtr<TrackBuffer> mAudioTrack;
   nsRefPtr<TrackBuffer> mVideoTrack;
 
-  MediaPromiseRequestHolder<AudioDataPromise> mAudioRequest;
-  MediaPromiseRequestHolder<VideoDataPromise> mVideoRequest;
+  MozPromiseRequestHolder<AudioDataPromise> mAudioRequest;
+  MozPromiseRequestHolder<VideoDataPromise> mVideoRequest;
 
-  MediaPromiseHolder<AudioDataPromise> mAudioPromise;
-  MediaPromiseHolder<VideoDataPromise> mVideoPromise;
+  MozPromiseHolder<AudioDataPromise> mAudioPromise;
+  MozPromiseHolder<VideoDataPromise> mVideoPromise;
 
-  MediaPromiseHolder<WaitForDataPromise> mAudioWaitPromise;
-  MediaPromiseHolder<WaitForDataPromise> mVideoWaitPromise;
-  MediaPromiseHolder<WaitForDataPromise>& WaitPromise(MediaData::Type aType)
+  MozPromiseHolder<WaitForDataPromise> mAudioWaitPromise;
+  MozPromiseHolder<WaitForDataPromise> mVideoWaitPromise;
+  MozPromiseHolder<WaitForDataPromise>& WaitPromise(MediaData::Type aType)
   {
     return aType == MediaData::AUDIO_DATA ? mAudioWaitPromise : mVideoWaitPromise;
   }
@@ -257,9 +257,9 @@ private:
 
   bool mForceVideoDecodeAhead;
 
-  MediaPromiseRequestHolder<SeekPromise> mAudioSeekRequest;
-  MediaPromiseRequestHolder<SeekPromise> mVideoSeekRequest;
-  MediaPromiseHolder<SeekPromise> mSeekPromise;
+  MozPromiseRequestHolder<SeekPromise> mAudioSeekRequest;
+  MozPromiseRequestHolder<SeekPromise> mVideoSeekRequest;
+  MozPromiseHolder<SeekPromise> mSeekPromise;
 
   // Temporary seek information while we wait for the data
   // to be added to the track buffer.
@@ -281,7 +281,7 @@ private:
   bool mHasEssentialTrackBuffers;
 
   void ContinueShutdown();
-  MediaPromiseHolder<ShutdownPromise> mMediaSourceShutdownPromise;
+  MozPromiseHolder<ShutdownPromise> mMediaSourceShutdownPromise;
 #ifdef MOZ_FMP4
   nsRefPtr<SharedDecoderManager> mSharedDecoderManager;
 #endif
diff --git a/dom/media/mediasource/SourceBuffer.h b/dom/media/mediasource/SourceBuffer.h
index aa3d387b748e..fd47270e93ac 100644
--- a/dom/media/mediasource/SourceBuffer.h
+++ b/dom/media/mediasource/SourceBuffer.h
@@ -7,7 +7,7 @@
 #ifndef mozilla_dom_SourceBuffer_h_
 #define mozilla_dom_SourceBuffer_h_
 
-#include "MediaPromise.h"
+#include "MozPromise.h"
 #include "MediaSource.h"
 #include "js/RootingAPI.h"
 #include "mozilla/Assertions.h"
@@ -195,7 +195,7 @@ private:
   uint32_t mUpdateID;
   int64_t mReportedOffset;
 
-  MediaPromiseRequestHolder<SourceBufferContentManager::AppendPromise> mPendingAppend;
+  MozPromiseRequestHolder<SourceBufferContentManager::AppendPromise> mPendingAppend;
   const nsCString mType;
 };
 
diff --git a/dom/media/mediasource/SourceBufferContentManager.h b/dom/media/mediasource/SourceBufferContentManager.h
index 9f6f526a2750..dff423b4e119 100644
--- a/dom/media/mediasource/SourceBufferContentManager.h
+++ b/dom/media/mediasource/SourceBufferContentManager.h
@@ -8,7 +8,7 @@
 #define MOZILLA_SOURCEBUFFERCONTENTMANAGER_H_
 
 #include "MediaData.h"
-#include "MediaPromise.h"
+#include "MozPromise.h"
 #include "MediaSourceDecoder.h"
 #include "SourceBuffer.h"
 #include "TimeUnits.h"
@@ -23,7 +23,7 @@ class SourceBufferContentManager {
 public:
   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(SourceBufferContentManager);
 
-  typedef MediaPromise<bool, nsresult, /* IsExclusive = */ true> AppendPromise;
+  typedef MozPromise<bool, nsresult, /* IsExclusive = */ true> AppendPromise;
   typedef AppendPromise RangeRemovalPromise;
 
   static already_AddRefed<SourceBufferContentManager>
diff --git a/dom/media/mediasource/TrackBuffer.cpp b/dom/media/mediasource/TrackBuffer.cpp
index f6ca03cc675e..5c2949c1c738 100644
--- a/dom/media/mediasource/TrackBuffer.cpp
+++ b/dom/media/mediasource/TrackBuffer.cpp
@@ -1093,7 +1093,7 @@ TrackBuffer::AbortAppendData()
     RemoveDecoder(current);
   }
   // The SourceBuffer would have disconnected its promise.
-  // However we must ensure that the MediaPromiseHolder handle all pending
+  // However we must ensure that the MozPromiseHolder handle all pending
   // promises.
   mInitializationPromise.RejectIfExists(NS_ERROR_ABORT, __func__);
 }
diff --git a/dom/media/mediasource/TrackBuffer.h b/dom/media/mediasource/TrackBuffer.h
index 75ba114bdf5b..f7bf11eeb39a 100644
--- a/dom/media/mediasource/TrackBuffer.h
+++ b/dom/media/mediasource/TrackBuffer.h
@@ -138,7 +138,7 @@ private:
   // Queue on the parent's decoder task queue a call to NotifyDataRemoved.
   void NotifyReaderDataRemoved(MediaDecoderReader* aReader);
 
-  typedef MediaPromise<bool, nsresult, /* IsExclusive = */ true> BufferedRangesUpdatedPromise;
+  typedef MozPromise<bool, nsresult, /* IsExclusive = */ true> BufferedRangesUpdatedPromise;
   nsRefPtr<BufferedRangesUpdatedPromise> UpdateBufferedRanges(Interval<int64_t> aByteRange, bool aNotifyParent);
 
   // Queue execution of InitializeDecoder on mTaskQueue.
@@ -226,15 +226,15 @@ private:
   MediaInfo mInfo;
 
   void ContinueShutdown();
-  MediaPromiseHolder<ShutdownPromise> mShutdownPromise;
+  MozPromiseHolder<ShutdownPromise> mShutdownPromise;
   bool mDecoderPerSegment;
   bool mShutdown;
 
-  MediaPromiseHolder<AppendPromise> mInitializationPromise;
+  MozPromiseHolder<AppendPromise> mInitializationPromise;
   // Track our request for metadata from the reader.
-  MediaPromiseRequestHolder<MediaDecoderReader::MetadataPromise> mMetadataRequest;
+  MozPromiseRequestHolder<MediaDecoderReader::MetadataPromise> mMetadataRequest;
 
-  MediaPromiseHolder<RangeRemovalPromise> mRangeRemovalPromise;
+  MozPromiseHolder<RangeRemovalPromise> mRangeRemovalPromise;
 
   Interval<int64_t> mLastAppendRange;
 
diff --git a/dom/media/mediasource/TrackBuffersManager.h b/dom/media/mediasource/TrackBuffersManager.h
index 22f0feba69bb..6b10eb084f39 100644
--- a/dom/media/mediasource/TrackBuffersManager.h
+++ b/dom/media/mediasource/TrackBuffersManager.h
@@ -34,7 +34,7 @@ using dom::SourceBufferAppendMode;
 
 class TrackBuffersManager : public SourceBufferContentManager {
 public:
-  typedef MediaPromise<bool, nsresult, /* IsExclusive = */ true> CodedFrameProcessingPromise;
+  typedef MozPromise<bool, nsresult, /* IsExclusive = */ true> CodedFrameProcessingPromise;
   typedef TrackInfo::TrackType TrackType;
   typedef MediaData::Type MediaType;
   typedef nsTArray<nsRefPtr<MediaRawData>> TrackBuffer;
@@ -166,7 +166,7 @@ private:
 
   void OnDemuxerInitDone(nsresult);
   void OnDemuxerInitFailed(DemuxerFailureReason aFailure);
-  MediaPromiseRequestHolder<MediaDataDemuxer::InitPromise> mDemuxerInitRequest;
+  MozPromiseRequestHolder<MediaDataDemuxer::InitPromise> mDemuxerInitRequest;
   bool mEncrypted;
 
   void OnDemuxFailed(TrackType aTrack, DemuxerFailureReason aFailure);
@@ -221,7 +221,7 @@ private:
     // buffer.
     bool mNeedRandomAccessPoint;
     nsRefPtr<MediaTrackDemuxer> mDemuxer;
-    MediaPromiseRequestHolder<MediaTrackDemuxer::SamplesPromise> mDemuxRequest;
+    MozPromiseRequestHolder<MediaTrackDemuxer::SamplesPromise> mDemuxRequest;
     // If set, position where the next contiguous frame will be inserted.
     // If a discontinuity is detected, it will be unset and recalculated upon
     // the next insertion.
@@ -272,10 +272,10 @@ private:
   void UpdateBufferedRanges();
   void RejectProcessing(nsresult aRejectValue, const char* aName);
   void ResolveProcessing(bool aResolveValue, const char* aName);
-  MediaPromiseRequestHolder<CodedFrameProcessingPromise> mProcessingRequest;
-  MediaPromiseHolder<CodedFrameProcessingPromise> mProcessingPromise;
+  MozPromiseRequestHolder<CodedFrameProcessingPromise> mProcessingRequest;
+  MozPromiseHolder<CodedFrameProcessingPromise> mProcessingPromise;
 
-  MediaPromiseHolder<AppendPromise> mAppendPromise;
+  MozPromiseHolder<AppendPromise> mAppendPromise;
   // Set to true while SegmentParserLoop is running. This is used for diagnostic
   // purposes only. We can't rely on mAppendPromise to be empty as it is only
   // cleared in a follow up task.
diff --git a/dom/media/moz.build b/dom/media/moz.build
index f7a009694a73..4ed5ee3973dd 100644
--- a/dom/media/moz.build
+++ b/dom/media/moz.build
@@ -124,7 +124,6 @@ EXPORTS += [
     'MediaFormatReader.h',
     'MediaInfo.h',
     'MediaMetadataManager.h',
-    'MediaPromise.h',
     'MediaQueue.h',
     'MediaRecorder.h',
     'MediaResource.h',
@@ -134,6 +133,7 @@ EXPORTS += [
     'MediaTimer.h',
     'MediaTrack.h',
     'MediaTrackList.h',
+    'MozPromise.h',
     'MP3Decoder.h',
     'MP3Demuxer.h',
     'MP3FrameParser.h',
diff --git a/dom/media/omx/AudioOffloadPlayer.h b/dom/media/omx/AudioOffloadPlayer.h
index 2ee3f454b84b..71b89a3ae013 100644
--- a/dom/media/omx/AudioOffloadPlayer.h
+++ b/dom/media/omx/AudioOffloadPlayer.h
@@ -146,10 +146,10 @@ private:
   // mLock
   SeekTarget mSeekTarget;
 
-  // MediaPromise of current seek.
+  // MozPromise of current seek.
   // Used in main thread and offload callback thread, protected by Mutex
   // mLock
-  MediaPromiseHolder<MediaDecoder::SeekPromise> mSeekPromise;
+  MozPromiseHolder<MediaDecoder::SeekPromise> mSeekPromise;
 
   // Positions obtained from offlaoded tracks (DSP)
   // Used in main thread and offload callback thread, protected by Mutex
diff --git a/dom/media/omx/MediaCodecReader.h b/dom/media/omx/MediaCodecReader.h
index 3f5b5e1decd9..ae4715825caa 100644
--- a/dom/media/omx/MediaCodecReader.h
+++ b/dom/media/omx/MediaCodecReader.h
@@ -178,10 +178,10 @@ protected:
 
   android::sp<android::MediaExtractor> mExtractor;
 
-  MediaPromiseHolder<MediaDecoderReader::MetadataPromise> mMetadataPromise;
+  MozPromiseHolder<MediaDecoderReader::MetadataPromise> mMetadataPromise;
   // XXX Remove after bug 1168008 land.
-  MediaPromiseRequestHolder<MediaResourcePromise> mMediaResourceRequest;
-  MediaPromiseHolder<MediaResourcePromise> mMediaResourcePromise;
+  MozPromiseRequestHolder<MediaResourcePromise> mMediaResourceRequest;
+  MozPromiseHolder<MediaResourcePromise> mMediaResourcePromise;
 
 private:
 
@@ -216,7 +216,7 @@ private:
   {
     AudioTrack();
     // Protected by mTrackMonitor.
-    MediaPromiseHolder<AudioDataPromise> mAudioPromise;
+    MozPromiseHolder<AudioDataPromise> mAudioPromise;
 
   private:
     // Forbidden
@@ -238,7 +238,7 @@ private:
     nsIntRect mPictureRect;
     gfx::IntRect mRelativePictureRect;
     // Protected by mTrackMonitor.
-    MediaPromiseHolder<VideoDataPromise> mVideoPromise;
+    MozPromiseHolder<VideoDataPromise> mVideoPromise;
 
     nsRefPtr<MediaTaskQueue> mReleaseBufferTaskQueue;
   private:
diff --git a/dom/media/omx/MediaOmxCommonReader.h b/dom/media/omx/MediaOmxCommonReader.h
index 1ff1554b6cbd..b2b90182e83e 100644
--- a/dom/media/omx/MediaOmxCommonReader.h
+++ b/dom/media/omx/MediaOmxCommonReader.h
@@ -24,7 +24,7 @@ class AbstractMediaDecoder;
 class MediaOmxCommonReader : public MediaDecoderReader
 {
 public:
-  typedef MediaPromise<bool /* aIgnored */, bool /* aIgnored */, /* IsExclusive = */ true> MediaResourcePromise;
+  typedef MozPromise<bool /* aIgnored */, bool /* aIgnored */, /* IsExclusive = */ true> MediaResourcePromise;
 
   MediaOmxCommonReader(AbstractMediaDecoder* aDecoder);
 
diff --git a/dom/media/omx/MediaOmxReader.h b/dom/media/omx/MediaOmxReader.h
index e0134cdb67fe..0eac90b2f0ee 100644
--- a/dom/media/omx/MediaOmxReader.h
+++ b/dom/media/omx/MediaOmxReader.h
@@ -44,11 +44,11 @@ class MediaOmxReader : public MediaOmxCommonReader
   // If mIsShutdown is false, and mShutdownMutex is held, then
   // AbstractMediaDecoder::mDecoder will be non-null.
   bool mIsShutdown;
-  MediaPromiseHolder<MediaDecoderReader::MetadataPromise> mMetadataPromise;
-  MediaPromiseRequestHolder<MediaResourcePromise> mMediaResourceRequest;
+  MozPromiseHolder<MediaDecoderReader::MetadataPromise> mMetadataPromise;
+  MozPromiseRequestHolder<MediaResourcePromise> mMediaResourceRequest;
 
-  MediaPromiseHolder<MediaDecoderReader::SeekPromise> mSeekPromise;
-  MediaPromiseRequestHolder<MediaDecoderReader::VideoDataPromise> mSeekRequest;
+  MozPromiseHolder<MediaDecoderReader::SeekPromise> mSeekPromise;
+  MozPromiseRequestHolder<MediaDecoderReader::VideoDataPromise> mSeekRequest;
 protected:
   android::sp<android::OmxDecoder> mOmxDecoder;
   android::sp<android::MediaExtractor> mExtractor;
@@ -113,7 +113,7 @@ public:
   android::sp<android::MediaSource> GetAudioOffloadTrack();
 
   // This method is intended only for private use but public only for
-  // MediaPromise::InvokeCallbackMethod().
+  // MozPromise::InvokeCallbackMethod().
   void ReleaseDecoder();
 
 private:
diff --git a/dom/media/omx/OmxDecoder.h b/dom/media/omx/OmxDecoder.h
index edf570b853f1..bcbae2476b7c 100644
--- a/dom/media/omx/OmxDecoder.h
+++ b/dom/media/omx/OmxDecoder.h
@@ -121,7 +121,7 @@ class OmxDecoder : public OMXCodecProxy::CodecResourceListener {
   // 'true' if a read from the audio stream was done while reading the metadata
   bool mAudioMetadataRead;
 
-  mozilla::MediaPromiseHolder<MediaResourcePromise> mMediaResourcePromise;
+  mozilla::MozPromiseHolder<MediaResourcePromise> mMediaResourcePromise;
 
   void ReleaseVideoBuffer();
   void ReleaseAudioBuffer();
diff --git a/dom/media/platforms/agnostic/eme/EMEDecoderModule.cpp b/dom/media/platforms/agnostic/eme/EMEDecoderModule.cpp
index f20e6bd04372..a1ea1edec172 100644
--- a/dom/media/platforms/agnostic/eme/EMEDecoderModule.cpp
+++ b/dom/media/platforms/agnostic/eme/EMEDecoderModule.cpp
@@ -17,7 +17,7 @@
 
 namespace mozilla {
 
-typedef MediaPromiseRequestHolder<CDMProxy::DecryptPromise> DecryptPromiseRequestHolder;
+typedef MozPromiseRequestHolder<CDMProxy::DecryptPromise> DecryptPromiseRequestHolder;
 
 static PLDHashOperator
 DropDecryptPromises(MediaRawData* aKey,