Make GrGLContext be uniquely owned.

Make GrGLContext take GrGLInterface by sk_sp

Change-Id: Iab11b27a7093ec897aaeeab9253958aeaa590b63
Reviewed-on: https://skia-review.googlesource.com/81701
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
4 files changed