Rename ScopedTaskEnvironment::ExecutionMode

ScopedTaskEnvironment::ExecutionMode is becoming
ScopedTaskEnvironment::ThreadPoolExecutionMode

This CL was uploaded by git cl split.

R=battre@chromium.org

Bug: 708584
Change-Id: I5afc5b29fc2c792223d09cdd8d223a0855e0b342
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1583805
Auto-Submit: Carlos Caballero <carlscab@google.com>
Reviewed-by: Dominic Battré <battre@chromium.org>
Commit-Queue: Dominic Battré <battre@chromium.org>
Cr-Commit-Position: refs/heads/master@{#654007}
1 file changed