Modify fontcache GM to actually spill atlas.

Adds an option to GrDrawOpAtlas to disable multitexturing.

Adds option to GrContextOptions to disable multitexturing for glyph atlases.


Change-Id: If413ab7061538fa0e75628d252be4fd14215b6ba
Reviewed-on: https://skia-review.googlesource.com/67802
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
8 files changed