Add AudioOutputController trace events and UMA backed wedge detection.

More extraction of debug code from my local test build.  This adds:
- Trace events for easy logging of AudioOutputController actions.
- A wedge detection UMA statistic for field monitoring.

BUG=160920
TEST=UMA stat is reported correctly when wedged and not.

Review URL: https://codereview.chromium.org/51003005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233034 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 233034
linux_aura: Improve window drag performance.

By delaying actually moving the window, we stop flooding the message
loop. This helps, but doesn't perfectly solve, the performance problems
with message dragging.

This patch adds a lot of TRACE_EVENT calls which were used to narrow
down exactly what was going on.

BUG=313903
R=ben@chromium.org, piman@chromium.org

Review URL: https://codereview.chromium.org/56053005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233035 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 233035