Add width and height option to SampleApp

So we can benchmark with given width/height dimensions.

Bug: skia:
Change-Id: I881c9f054cdcecc3e0b2bfb600afd778e1c57d95
Reviewed-on: https://skia-review.googlesource.com/51246
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Yuqian Li <liyuqian@google.com>
9 files changed