Parse matroska clusters incrementally as opposed to all at once.

While the patch is ugly, it prevents us from downloading the entire first cluster during the call to av_find_stream_info(). As a result, start up latency is greatly improved.

BUG=100439
TEST=start up time, seeking, everything works

Review URL: http://codereview.chromium.org/8296016

git-svn-id: http://src.chromium.org/svn/trunk/deps/third_party/ffmpeg/source@105638 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
1 file changed