Fix event tracing for windows test flakyness.
Assert on non-null properties to the static members of the trace controller.
Fix usage of same.
Add a PostEventsDisabled method to trace producer to which allows for a non-racy enable/disable test.

BUG=52388
BUG=59328
TEST=Unittests in the change.

Review URL: http://codereview.chromium.org/3800006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@62766 0039d316-1c4b-4281-b951-d872f2087c98
6 files changed