Add Optional COM MTA Support to All SchedulerWorkerPoolImpl Threads

This change initializes the Windows Runtime as an MTA for versions at
or above Windows 8 and COM as an MTA for versions below Windows 8 if
the caller requests for COM MTA.

BUG=706479

Change-Id: I55e08bb270ac9d1ebbce35647e8ae23ec8504f95
Reviewed-on: https://chromium-review.googlesource.com/741455
Commit-Queue: Robert Liao <robliao@chromium.org>
Reviewed-by: François Doray <fdoray@chromium.org>
Cr-Commit-Position: refs/heads/master@{#513235}

CrOS-Libchrome-Original-Commit: 4393dc6bad8f81e44ef2d7eb40e8da3510aabfba
7 files changed
tree: 00c3c3cae46a7cb09bfbe47f1e3a3b191d2a3699
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/