[FFmpeg-devel] avcodec/apng: Dispose previous frame properly

[Donny Yang]

[PATCH 1/2] avcodec/apng: Remove threading support
[PATCH 2/2] avcodec/apng: Dispose previous frame properly

Patches have been tested against:
 - https://people.mozilla.org/~dolske/apng/
 - http://littlesvr.ca/apng/images/clock.png
 - http://upload.wikimedia.org/wikipedia/commons/1/14/Animated_PNG_example_bouncing_beach_ball.png

Before these patches, the last two test files did not decode properly