GitLab

XP seems to be lowering the priority of the thread responding to
audio callbacks when backgrounded, causing glitching.

BUG=161307
TEST=background playback on XP works without issue.

Review URL: https://codereview.chromium.org/11316284

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@170870 0039d316-1c4b-4281-b951-d872f2087c98