Split GrDawnImageInfo into GrDawnTextureInfo and GrDawnRenderTargetInfo.
The former holds only a wgpu::Texture, and the latter holds only a
wgpu::TextureView. This split is necessary because Dawn SwapChains now
vend TextureViews, not Textures.
The TextureView held by GrDawnRenderTargetInfo is always 1-mip, since
it's a requirement for rendering to a texture in Dawn.
Change-Id: Id6e99b5e4bf18f97e939170856a665e2038253ea
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/254810
Commit-Queue: Stephen White <senorblanco@chromium.org>
Reviewed-by: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
f03c116021