Bug 1416643. P2 - always access mDidNotifyDataEnded within the lock. r=bechen,gerald

MozReview-Commit-ID: 3us659lCEZE

--HG--
extra : rebase_source : 9deace7a2e83ae42132f593bb7c638c5e2977638

dom/media/MediaCache.cpp

@@ -481,7 +481,6 @@ MediaCacheStream::MediaCacheStream(ChannelMediaResource* aClient,
                                    bool aIsPrivateBrowsing)
   : mMediaCache(nullptr)
   , mClient(aClient)
-  , mDidNotifyDataEnded(false)
   , mIsTransportSeekable(false)
   , mCacheSuspended(false)
   , mChannelEnded(false)
@@ -2704,6 +2703,8 @@ MediaCacheStream::InitAsClone(MediaCacheStream* aOriginal)
   MOZ_ASSERT(!mMediaCache, "Has been initialized.");
   MOZ_ASSERT(aOriginal->mMediaCache, "Don't clone an uninitialized stream.");
 
+  ReentrantMonitorAutoEnter mon(aOriginal->mMediaCache->GetReentrantMonitor());
+
   if (aOriginal->mDidNotifyDataEnded &&
       NS_FAILED(aOriginal->mNotifyDataEndedStatus)) {
     // Streams that ended abnormally are ineligible for cloning.
@@ -2719,8 +2720,6 @@ MediaCacheStream::InitAsClone(MediaCacheStream* aOriginal)
   mResourceID = aOriginal->mResourceID;
 
   // Grab cache blocks from aOriginal as readahead blocks for our stream
-  ReentrantMonitorAutoEnter mon(mMediaCache->GetReentrantMonitor());
-
   mPrincipal = aOriginal->mPrincipal;
   mStreamLength = aOriginal->mStreamLength;
   mIsTransportSeekable = aOriginal->mIsTransportSeekable;

dom/media/MediaCache.h

@@ -453,8 +453,6 @@ private:
 
   // These fields are main-thread-only.
   nsCOMPtr<nsIPrincipal> mPrincipal;
-  // True if CacheClientNotifyDataEnded has been called for this stream.
-  bool                   mDidNotifyDataEnded;
 
   // The following fields must be written holding the cache's monitor and
   // only on the main thread, thus can be read either on the main thread
@@ -503,6 +501,8 @@ private:
   // The number of times this stream has been Pinned without a
   // corresponding Unpin
   uint32_t          mPinCount;
+  // True if CacheClientNotifyDataEnded has been called for this stream.
+  bool              mDidNotifyDataEnded = false;
   // The status used when we did CacheClientNotifyDataEnded. Only valid
   // when mDidNotifyDataEnded is true.
   nsresult          mNotifyDataEndedStatus;