[graphite] Make GrBlend shareable between Graphite and Ganesh
Additionally make the enums enum-classes.
We will need this to specify fixed function blend modes in Graphite.
This CL is mainly mechanical (i.e., global replace) but some fix-ups were required for our internal bit twiddling with the enum-classes.
Bug: skia:12701
Change-Id: I67abcf8274d14e691974cf253bf65dcb4697bd9a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/515318
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
26 files changed
