From https://www.khronos.org/registry/gles/api/GLES2/gl2ext.h

BUG=angleproject:1553

Change-Id: I3a0e5ee77de3db02eace63d40df7db040a739f88
Reviewed-on: https://chromium-review.googlesource.com/423434Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>