Remove caps-accessor function pointers from SkSL::Setting.
Remove caps-accessor function pointers from SkSL::Setting.

We have a TODO to get rid of the accessor functions. We can use direct
member pointers instead.

Change-Id: I81470d8e03905be583677ef41a6de3547c8b318e
Bug: skia:12559
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/547823
Auto-Submit: John Stiles <f4fcf42d3bb5924557f1eeb3be66747535e585da@google.com>
Reviewed-by: Brian Osman <794c0b5534edf5601d88e1d41975d0262da12894@google.com>
Commit-Queue: John Stiles <f4fcf42d3bb5924557f1eeb3be66747535e585da@google.com>

google/skia,google/skia,google/skia,google/skia,google/skia,google/skia,google/skia,google/skia,google/skia,google/skia