Bug 1481176 - P4. Make CanHandleMediaType usable off the main thread. r=bryce

This is done by ensuring that all methods is called are usable off the main thread and creating the required preference accessors.

Differential Revision: https://phabricator.services.mozilla.com/D2790

dom/media/DecoderTraits.cpp

@@ -154,8 +154,6 @@ CanPlayStatus
 CanHandleMediaType(const MediaContainerType& aType,
                    DecoderDoctorDiagnostics* aDiagnostics)
 {
-  MOZ_ASSERT(NS_IsMainThread());
-
 #ifdef MOZ_ANDROID_HLS_SUPPORT
   if (HLSDecoder::IsSupportedType(aType)) {
     return CANPLAY_MAYBE;

dom/media/MediaDecoder.cpp

@@ -18,6 +18,7 @@
 #include "mozilla/FloatingPoint.h"
 #include "mozilla/MathAlgorithms.h"
 #include "mozilla/Preferences.h"
+#include "mozilla/StaticPrefs.h"
 #include "mozilla/StaticPtr.h"
 #include "mozilla/Telemetry.h"
 #include "Visibility.h"
@@ -1265,25 +1266,25 @@ MediaDecoder::SetCDMProxy(CDMProxy* aProxy)
 bool
 MediaDecoder::IsOpusEnabled()
 {
-  return Preferences::GetBool("media.opus.enabled");
+  return StaticPrefs::MediaOpusEnabled();
 }
 
 bool
 MediaDecoder::IsOggEnabled()
 {
-  return Preferences::GetBool("media.ogg.enabled");
+  return StaticPrefs::MediaOggEnabled();
 }
 
 bool
 MediaDecoder::IsWaveEnabled()
 {
-  return Preferences::GetBool("media.wave.enabled");
+  return StaticPrefs::MediaWaveEnabled();
 }
 
 bool
 MediaDecoder::IsWebMEnabled()
 {
-  return Preferences::GetBool("media.webm.enabled");
+  return StaticPrefs::MediaWebMEnabled();
 }
 
 NS_IMETHODIMP

dom/media/mp4/MP4Decoder.cpp

@@ -199,7 +199,7 @@ MP4Decoder::IsAAC(const nsACString& aMimeType)
 bool
 MP4Decoder::IsEnabled()
 {
-  return StaticPrefs::mediaMp4Enabled();
+  return StaticPrefs::MediaMp4Enabled();
 }
 
 /* static */ nsTArray<UniquePtr<TrackInfo>>

dom/media/ogg/OggDecoder.cpp

@@ -7,8 +7,8 @@
 #include "OggDecoder.h"
 #include "MediaContainerType.h"
 #include "MediaDecoder.h"
-#include "nsMimeTypes.h"
 #include "mozilla/StaticPrefs.h"
+#include "nsMimeTypes.h"
 
 namespace mozilla {
 

dom/media/webm/WebMDecoder.cpp

@@ -85,7 +85,7 @@ WebMDecoder::GetTracksInfo(const MediaContainerType& aType, MediaResult& aError)
 bool
 WebMDecoder::IsSupportedType(const MediaContainerType& aContainerType)
 {
-  if (!Preferences::GetBool("media.webm.enabled")) {
+  if (!StaticPrefs::MediaWebMEnabled()) {
     return false;
   }
 

modules/libpref/init/StaticPrefList.h

@@ -880,6 +880,20 @@ VARCACHE_PREF(
 )
 #undef PREF_VALUE
 
+// Opus
+VARCACHE_PREF(
+  "media.opus.enabled",
+   MediaOpusEnabled,
+  RelaxedAtomicBool, true
+)
+
+// Wave
+VARCACHE_PREF(
+  "media.wave.enabled",
+   MediaWaveEnabled,
+  RelaxedAtomicBool, true
+)
+
 // Ogg
 VARCACHE_PREF(
   "media.ogg.enabled",
@@ -887,6 +901,13 @@ VARCACHE_PREF(
   RelaxedAtomicBool, true
 )
 
+// WebM
+VARCACHE_PREF(
+  "media.webm.enabled",
+   MediaWebMEnabled,
+  RelaxedAtomicBool, true
+)
+
 // AV1
 VARCACHE_PREF(
   "media.av1.enabled",
@@ -920,7 +941,7 @@ VARCACHE_PREF(
 #endif
 VARCACHE_PREF(
   "media.mp4.enabled",
-   mediaMp4Enabled,
+   MediaMp4Enabled,
   RelaxedAtomicBool, PREF_VALUE
 )
 #undef PREF_VALUE