Add new thin anti-aliasing demo

Bug: skia:
Change-Id: I3c29dee38f6fb43a2d1d5d429193fcf4a719a2cb
Reviewed-on: https://skia-review.googlesource.com/c/186863
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
2 files changed