Add cache for handling of contexts.

Added scaler context cache on the Renderer side that
maps descriptors to scaler contexts.

Added preliminary timing code.

Remove unused print statements.

BUG=skia:7515

Change-Id: I156ba656aab113e0ceae0c2ea0f9f3c1d3d61d6a
Reviewed-on: https://skia-review.googlesource.com/99540
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Herb Derby <herb@google.com>
2 files changed