GitLab

The --disable-best-effort-tasks switch was only read when a task
execution fence was created. This CL ensure that it is read even if
there is no task execution fence. It also adds a test to verify the
behavior and avoid future regressions.

The TabCapturePerformanceTest.Performance test used
--disable-best-effort-tasks to ensure that the test can pass without
BEST_EFFORT tasks. Prior to this CL, this flag only prevented
BEST_EFFORT tasks from running in the browser process. With this CL, it
also prevents BEST_EFFORT tasks from running in renderers and utility
processes. Since the test needs BEST_EFFORT tasks to run in utility
processes for tracing, this CL changes --disable-best-effort-tasks
to ScopedBestEffortExecutionFence. The ScopedBestEffortExecutionFence
only prevents BEST_EFFORT tasks from running in the process where it
is used (keeps the test's existing behavior).

Bug: 839110
Change-Id: I4ef104ccabb81840cbb48d309e1ed3baaa20feda
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1872654Reviewed-by: Yuri Wiitala <miu@chromium.org>
Reviewed-by: Gabriel Charette <gab@chromium.org>
Commit-Queue: François Doray <fdoray@chromium.org>
Auto-Submit: François Doray <fdoray@chromium.org>
Cr-Commit-Position: refs/heads/master@{#711676}