SH_GLSL_COMPATIBILITY_OUTPUT.

BUG=angleproject:1277

Change-Id: Ib820a46151637e8c61e94b966b970de46ccca6b9
Reviewed-on: https://chromium-review.googlesource.com/323160Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tryjob-Request: Jamie Madill <jmadill@chromium.org>
Tested-by: Ian Ewell <ewell@google.com>