[graphite] Move tiled image drawing utilities to their own file(s)

This is as mechanical a move as I could make it. The main change is
passing 'draw_image' to DrawTiledBitmap.

Bug: b/267656937
Change-Id: Ibf8f1c41bb59d1c4dc8658c12c1914bdaa2804b4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/701976
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
6 files changed