[graphite] Rework Device::drawSpecial

This reroutes drawSpecial through drawImageRect reducing the number of code paths we need to support.

Bug: b/241427862
Change-Id: I3c2a737152e834921c4f89a84db6e292c7a821a4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/576438
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
3 files changed