Use common fallback code for drawing an SkGlyphRun

This reorganizes the code so that Mask, SDFT and Paths
share calling the fallback code. It also orders the
different drawing methods from most frequent to least.

Change-Id: I1bbfc92765682c6a20d59da34734f127a6d017cb
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/249558
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Herb Derby <herb@google.com>
1 file changed