Remove GrDirectContext::ComputeImageSize. Use SkImage::textureSize.

Bug: skia:11208
Change-Id: Ie5f56b6d168ab43189be75bb2be60b315e724569
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/371958
Commit-Queue: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
Auto-Submit: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
3 files changed