Remove #ifdef SK_GL from GrDirectContext by moving MakeGL factories

Follow-on CLs will migrate Skia's and clients' call sites to
the now-deprecated APIs.

Change-Id: I3502e697ca7d851358360784ede4261d07fed32e
Bug: b/293490566
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/760017
Reviewed-by: Brian Osman <brianosman@google.com>
11 files changed