Cleanup interface between SkGlyphRunPainter and SkDraw

  - Remove unused paramaters
  - Unify the handling of paint
  - Simplify using ensureBitmapBuffers
  - Rename misc.

Change-Id: Id1100765f5f12fef3e5a8c1f0ce0f44cfb60ae2d
Reviewed-on: https://skia-review.googlesource.com/c/166482
Commit-Queue: Herb Derby <herb@google.com>
Auto-Submit: Herb Derby <herb@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
3 files changed