Add `Canvas.quickReject` to quickly tell if a Rect is within the clip

Change-Id: I72fe7c22c863992519c47e54b26528c1ae5390f1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/903702
Reviewed-by: Kaylee Lubick <kjlubick@google.com>
Commit-Queue: Harry Terkelsen <het@google.com>
8 files changed