[graphite] Remove custom glue code for local matrix and blend shaders
We now pass the child output variable names into the snippet code after
all the uniforms.
This leaves the following 3 custom glue code generators:
GenerateImageShaderGlueCode -- sampler
GenerateFixedFunctionBlenderGlueCode -- prior stage's output
GenerateShaderBasedBlenderGlueCode -- dst read & prior stage's output
Bug: skia:12701
Change-Id: I9185d8f292cc45d351218b95fa6d7d70d639e2f6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/536098
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
4 files changed
