Support GL_ANGLE_texture_rectangle.

Change-Id: Ibe75da5f7f8d1f399f340acf186da353a7c46485
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/213424
Commit-Queue: Robert Phillips <robertphillips@google.com>
Auto-Submit: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
2 files changed