Revert "Revert "Revert "Remove GrBackendRenderTargetDesc in favor of GrBackendRenderTarget."""

This reverts commit 71554bc256b705fe959b7aa2fb2f24ed48782362.

Reason for revert: Google3

Original change's description:
> Revert "Revert "Remove GrBackendRenderTargetDesc in favor of GrBackendRenderTarget.""
> 
> This reverts commit 807371c15bd742efb98a9df6e1dee73e8bda8af5.
> 
> Docs-Preview: https://skia.org/?cl=40260
> Change-Id: I28e0434c455155ff39a5aaa4141abdf442474e87
> Reviewed-on: https://skia-review.googlesource.com/40260
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>

TBR=egdaniel@google.com,bsalomon@google.com

Change-Id: Ifdfa896a70db69935473276d12dce54de5c6b6f7
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/41500
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
12 files changed