Add general quad methods to GrRTC

Refactor compositor GM to use GrRTC directly instead of adding draw ops.
Adds a test row for using drawTextureSet now that it takes dst clips.

Bug: skia:
Change-Id: I6863ef1286cab0f0e5cf989e4aaef8ff2ca0abb8
Reviewed-on: https://skia-review.googlesource.com/c/193023
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
6 files changed