Attempt both GL and GLES for GPU unit tests

The hardcoded logic was not all inclusive and caused Chromebooks to
not run GPU unit tests.

Bug: skia:
Change-Id: I7688adab314d12234ee03363609a1c4bf8f2edb5
Reviewed-on: https://skia-review.googlesource.com/55561
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
1 file changed