Add GM that draws vertices, atlas, and patch with runtime colorfilter

Make CPU drawVertices and drawAtlas use SkVM if a SkRasterPipeline
blitter creation fails (e.g. due to runtime color filter).

Change-Id: Ib272f58cb729b7047e5c48eba866b435f4e075a3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/469903
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
3 files changed