Bug 654787 - part7: Stop playing and decoding when looping is cancelled; r=jwwang

MozReview-Commit-ID: BQKVsmDSqpJ

--HG--
extra : rebase_source : 64377f37dd6d1fd2a7a550843ffc805688a4d488

dom/media/MediaDecoderStateMachine.cpp

@@ -608,27 +608,7 @@ public:
     mOnVideoPopped.DisconnectIfExists();
   }
 
-  void Step() override
-  {
-    if (mMaster->mPlayState != MediaDecoder::PLAY_STATE_PLAYING &&
-        mMaster->IsPlaying()) {
-      // We're playing, but the element/decoder is in paused state. Stop
-      // playing!
-      mMaster->StopPlayback();
-    }
-
-    // Start playback if necessary so that the clock can be properly queried.
-    if (!mIsPrerolling) {
-      mMaster->MaybeStartPlayback();
-    }
-
-    mMaster->UpdatePlaybackPositionPeriodically();
-
-    MOZ_ASSERT(!mMaster->IsPlaying() || mMaster->IsStateMachineScheduled(),
-               "Must have timer scheduled");
-
-    MaybeStartBuffering();
-  }
+  void Step() override;
 
   State GetState() const override
   {
@@ -2311,6 +2291,51 @@ DecodingState::Enter()
   }
 }
 
+void
+MediaDecoderStateMachine::
+DecodingState::Step()
+{
+  if (mMaster->mPlayState != MediaDecoder::PLAY_STATE_PLAYING &&
+      mMaster->IsPlaying()) {
+    // We're playing, but the element/decoder is in paused state. Stop
+    // playing!
+    mMaster->StopPlayback();
+  }
+
+  // Start playback if necessary so that the clock can be properly queried.
+  if (!mIsPrerolling) {
+    mMaster->MaybeStartPlayback();
+  }
+
+  TimeUnit before = mMaster->GetMediaTime();
+  mMaster->UpdatePlaybackPositionPeriodically();
+
+  // After looping is cancelled, the time won't be corrected, and therefore we
+  // can check it to see if the end of the media track is reached.
+  TimeUnit adjusted = mMaster->GetClock();
+  Reader()->AdjustByLooping(adjusted);
+  // Make sure the media is started before comparing the time, or it's
+  // meaningless. Without checking IsStarted(), the media will be terminated
+  // immediately after seeking forward. When the state is just transited from
+  // seeking state, GetClock() is smaller than GetMediaTime(), since
+  // GetMediaTime() is updated upon seek is completed while GetClock() will be
+  // updated after the media is started again.
+  if (mMaster->mMediaSink->IsStarted() && !mMaster->mLooping &&
+      adjusted < before) {
+    mMaster->StopPlayback();
+    mMaster->mAudioDataRequest.DisconnectIfExists();
+    AudioQueue().Finish();
+    mMaster->mAudioCompleted = true;
+    SetState<CompletedState>();
+    return;
+  }
+
+  MOZ_ASSERT(!mMaster->IsPlaying() || mMaster->IsStateMachineScheduled(),
+             "Must have timer scheduled");
+
+  MaybeStartBuffering();
+}
+
 void
 MediaDecoderStateMachine::
 DecodingState::HandleEndOfAudio()
@@ -3480,7 +3505,7 @@ MediaDecoderStateMachine::UpdatePlaybackPositionPeriodically()
     // Once looping was turned on, the time is probably larger than the duration
     // of the media track, so the time over the end should be corrected.
     mReader->AdjustByLooping(clockTime);
-    bool loopback = clockTime < GetMediaTime();
+    bool loopback = clockTime < GetMediaTime() && mLooping;
 
     // Skip frames up to the frame at the playback position, and figure out
     // the time remaining until it's time to display the next frame and drop