Use just GrSurfaceProxy in pipeline management.

Replaces VisitSurfaceProxyFunc with GrOp::VisitProxyFunc since they are
now the same.

Records sampled textures as GrSurfaceProxies, but asserts they are in fact
texturable. Updates all backends to process the pipelines with surface
proxies (which always have had to do a surface->asTexture() virtual call
that is unchanged, this just avoids the unnecessary proxy virtual).

Also updates the GrTextureOp to not call asTextureProxy() anymore, to
take advantage of the relaxed pipeline types.

A number of instances of asTextureProxy() remain. It is still the primary
method of determining if a proxy is texturable, so code paths that branch
on that still use it. Some resource management code still requires mipmap
functionality specific to the GrTextureProxy API, so they still use it.

To keep this CL sane, the GrFP::TextureSampler and all generated FPs have
not been updated to use GrSurfaceProxy, although that will be in a follow
up since it should be technically possible.

Bug: skia:9556
Change-Id: I1e917aff9e70b08915e98ccc17c6b8f3be29c4f6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/255830
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
53 files changed