fold params into StageRec

pre-CL before trying to add a hint-rect field to allow shaders to "optimize"
their stages for a given restriction in device space
- e.g. if the shader's intrinsic domain is contained, it won't need to tile/clamp


Bug: skia:
Change-Id: Ia2da557691da25f31e4b9e3f53c3bc6709b89083
Reviewed-on: https://skia-review.googlesource.com/40224
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Reed <reed@google.com>
19 files changed