Move clear-as-draw workaround to GrGLGpu and expose via GrContextOptions.


Bug: skia:7154
Change-Id: I23ffc11dab4a377fbd6b7e4e33722b3fa0793d58
Reviewed-on: https://skia-review.googlesource.com/60681
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
14 files changed