Run WebGL conformance using ANGLE on Android.

Test that the ANGLE backend flags passed to the browser are used.

BUG=882580

Change-Id: I051859cdedad65d6eb304931644010d8b3bdb5a6
Reviewed-on: https://chromium-review.googlesource.com/c/1299551
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#613705}
10 files changed