Remove bridge code for legacy GL GrBackendSurface code

While doing this, I ran into a small #include issue with
GrGLGpu, so I enforced IWYU on it.

Client CLs:
 - https://crrev.com/c/4739911
 - http://cl/553620143
 - http://cl/553628593
 - http://cl/553637942
 - http://cl/553705311
 - http://cl/553821763
 - http://cl/553837992
 - http://ag/24343000
 - http://ag/24343454
 - http://ag/24420576
 - http://ag/24445187
 - https://github.com/flutter/engine/pull/44334
 - https://github.com/flutter/engine/pull/44682

Change-Id: If07cbe3a60593810911c147b8a81e30459623f28
Bug: b/293490566
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/741437
Reviewed-by: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
7 files changed