Adds SkRuntimeEffect, a ref-counted object to hold SkSL,
a Compiler, and compiled Program, along with uniform info.
Removes the old SkSLFP factory and factory cache types.
Caching is done by simply holding on to the effect (or
the shader/color filter factories, which own an effect).
The effect class is simply ref'd by the factories, the
shader and color filter types, and the FP.
NOTE: Changes to public headers only affect private functions.
Change-Id: I0c1401505cb234e83943ad4ef2db6680f4c69fb9
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/259336
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
7b1678a527