GitLab

Per Matroska spec difference between frames timestamps must be used as
block duration when neither Duration nor DefaultDuration is specified.
Problem was that WebMClusterParser was waiting for the next frame
even when DefaultDuration is specified.

BUG=338529

Review URL: https://codereview.chromium.org/230173002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@263097 0039d316-1c4b-4281-b951-d872f2087c98