More GrGLFormat.

Also rename from GrGLSizedInternalFormat since the compressed formats
aren't really sized internal formats.

Change-Id: I8744f1f4b8156300ab69d89066b44913bce120a3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/226956
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
7 files changed