Remove the skip-draw xp optimization

This seems like extra complexity for a impractical case. Also, if this is important a lot more work could be saved by catching this upstack (e.g. SkCanvas or SkPaintToGrPaint).

Change-Id: Ib47be9f3cdc8ce9e5b12d9e9eac5266f04c337a9
Reviewed-on: https://skia-review.googlesource.com/8949
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
4 files changed