Add a simple FPS meter to CanvasKit viewer

Change-Id: I7577f9634afd2555543ca56ca774219724b90ce8
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/279206
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
1 file changed