Remove remaining functions in GrGLCaps that use GrPixelConfig.

At this point this just leaves the function that converts a GrBackendFormat
to a GrPixelConfig. This function will probably need to live until we
fully remove GrPixelConfig.

Also removed the bgraIsInternalFormat call since we literally have the format
so we can just straight up check if it is bgra or not.

Bug: skia:6718
Change-Id: I917d9361b590d69baeb0f6a5e1e5dae6908f09ad
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/234658
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
2 files changed