Rename ScopedTaskEnvironment::ExecutionMode

ScopedTaskEnvironment::ExecutionMode is becoming
ScopedTaskEnvironment::ThreadPoolExecutionMode

This CL was uploaded by git cl split.

R=chrisha@chromium.org

Bug: 708584
Change-Id: I6bcdb884152e9e96127cf064320e555c58794d7f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1583757
Auto-Submit: Carlos Caballero <carlscab@google.com>
Reviewed-by: Chris Hamilton <chrisha@chromium.org>
Commit-Queue: Chris Hamilton <chrisha@chromium.org>
Cr-Commit-Position: refs/heads/master@{#654010}
1 file changed