Performance tuning of HandleWatcher

Couple of tweaks:
. make WatcherThreadManager maintain a queue of requests and process
  them at once.
. Makes State not unnecessarily cancel requests if it was told the
  handle is ready.

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

Review URL: https://codereview.chromium.org/480293004

Cr-Commit-Position: refs/heads/master@{#291436}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@291436 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: 4faacf020ba2ae2ec4efd7685d474ff9f183d36a
1 file changed
tree: fb0dfccbe29ec93e39f8b76fcfeb98a17922a655
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/