GitLab

Currently, GLFenceEGL's ClientWait always uses EGL_FOREVER_KHR. This change
adds a way to specify a timeout so that a thread can yield to do other work
while waiting.

This is being used in the critical path for WebVR rendering, and even a 1ms
delay noticeably cuts into the 16ms frame time budget. The workaround was to
repeatedly poll checking for completion, but that needs a very aggressive
timeout to avoid unnecessary delay. Using a timeout is more efficient.

Bug: 726026
Change-Id: I4c4292f31cf472e538cfdf18a835d48226d6ac58
Reviewed-on: https://chromium-review.googlesource.com/572663Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Michael Thiessen <mthiesse@chromium.org>
Commit-Queue: Klaus Weidner <klausw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487159}