Add new GMs to stress rendering of many circles and rrects

Change-Id: I060419bc39484b379329a1691e199d9d3db9c808
Reviewed-on: https://skia-review.googlesource.com/8807
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
3 files changed