Reland "Consolidate texture uploads in GrGLGpu."

This is a reland of 5c66aa744a2d27057837f42abce4b0d9e38ba9ce

Original change's description:
> Consolidate texture uploads in GrGLGpu.
> 
> Remove unused GrMipMapsStatus out param
> 
> All paths now unbind PBO before upload.
> 
> Use the backend texture's target in GrGLGpu::onUpdateBackendTexture.
> 
> Change-Id: I91ce483841c8f8b2cc8a2e1f1a45a186a66d2d5f
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/289576
> Commit-Queue: Brian Salomon <bsalomon@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>

Change-Id: Ic5ecff8c7a2fb1c03c6ec451d73ade437c884e96
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/290131
Auto-Submit: Brian Salomon <bsalomon@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
3 files changed