Implement GL canCopySurface in GrGLCaps.

Bug: skia:
Change-Id: Ibd55a5a5e62121f58ef7c5148a54aaad6fdcd243
Reviewed-on: https://skia-review.googlesource.com/125480
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
5 files changed