[graphite] Remove legacy quad rendering flag

Bug: b/307950537
Change-Id: I8efa2fe2467546c331bf6da0581c9dc6cffc2139
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/773942
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
1 file changed