Disallow breakaway from job on Windows 8, which supports nested jobs

BUG=371406, 392108
R=sky@chromium.org

Review URL: https://codereview.chromium.org/467673002

git-svn-id: http://src.chromium.org/svn/trunk/src/base@289523 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
base: Factor task debug annotations out of MessageLoop

The MessageLoop has some code for adding debug annotations such as trace
flows and memory usage tags to posted tasks. Since we want to use these
annotations more generally for tasks that are scheduled outside the base
message loop, this patch factors it out into a standalone class.

TEST=TaskAnnotatorTest
BUG=391005

Review URL: https://codereview.chromium.org/455833004

git-svn-id: http://src.chromium.org/svn/trunk/src/base@289560 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Adds some CHECKs to MessagePumpMojo

The thread watcher appears to be kicking on when we're trying to
remove a handle. Not sure why. This converts some DCHECKs to CHECKs
and fixes handling of the deadline. I suspect none of this will help,
but it's worth a shot.

BUG=399769
TEST=none
R=darin@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=288949

Review URL: https://codereview.chromium.org/454433003

git-svn-id: http://src.chromium.org/svn/trunk/src/base@289600 4ff67af0-8c30-449e-8e8b-ad334ec8d88c