Timothy Nikkel c39b7fb81b Bug 1443232. Don't insert frames into our AnimationFrameBuffer that we consider in error and unusable. r=aosmond ...

After decoding the first frame we allocate the second frame, but before it finishes we encounter an error, Decoder::PostError is called it aborts the second frame and decrements the frame count. But AnimationSurfaceProvider::CheckForFrameAtTerminalState just asks for the current frame ref from the decoder (which it never cleared) and inserts that.

The condition that we use from the decoder to decide to report a new frame is mFinishedNewFrame (via TakeCompleteFrameCount), however this doesn't directly correspond to mFrameCount. So we create a new bool on the Decoder to track when there is a frame that we can take.

This didn't cause any problems before but now we have tighter coupling between the list of frames the AnimationSurfaceProvider has and what FrameAnimator expects.

Another possible fix would be to clear the current frame ref in PostError, but the only place we clear the current frame is when we allocate the new frame and we have the mImageData pointer still around that decoders could theorhetically use to do final processing on the last partial frame.

2018-03-08 17:33:04 -06:00

16 KiB

Raw Blame History

View Raw