Get GrBackendRenderTarget's sample count from MtlTexture.
Instead of being passed separately.
Check sample count in various onWrap methods in GrMtlGpu.
Bug: skia:9832
Cq-Include-Trybots: luci.skia.skia.primary:Test-iOS-Clang-iPhone8-GPU-AppleA11-arm64-Release-All-Metal,Test-iOS-Clang-iPhone7-GPU-PowerVRGT7600-arm64-Release-All-Metal,Test-iOS-Clang-iPadPro-GPU-PowerVRGT7800-arm64-Release-All-Metal,Test-iOS-Clang-iPhone11-GPU-AppleA13-arm64-Release-All-Metal,Test-iOS-Clang-iPhone6-GPU-PowerVRGX6450-arm64-Release-All-Metal,Test-Mac10.15-Clang-MacBookAir7.2-GPU-IntelHD6000-x86_64-Release-All-Metal
Change-Id: If5813db95b07f5d272e80920486f461cc5a587fc
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/320956
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
8 files changed