Clean up some "const SkISize& dimensions" usages w/in Ganesh

This is pulled out of the parameter reordering CL - which has become too large.

Change-Id: Id36875dd4a670611ab94a08a3a6df41c474e9022
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/266217
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
12 files changed