arc: Switch from BlockingPool to TaskScheduler

BUG=667892

Change-Id: Ic1113e7da8020f4529a554a9d4483a147ebc59be
Reviewed-on: https://chromium-review.googlesource.com/549521
Commit-Queue: Ryo Hashimoto <hashimoto@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#482567}
1 file changed