MotionMarkSlide: make sure we enable AA for canvas tests.

Canvas2D is generally AA-only so we should be running in that mode.

Change-Id: Ia78934616bb162d510ca182cb6f0d53871045758
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/807816
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Auto-Submit: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
1 file changed