Refactor attempting shader compilation with different flags.

BUG=angle:648

Change-Id: Ie340eaa708820cc13be6d1f5ba04555b6c1918ea
Reviewed-on: https://chromium-review.googlesource.com/199310
Tested-by: Nicolas Capens <nicolascapens@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
4 files changed