This class does not appear to have any external users, and Skia probably
does not want anyone depending on it. It also clutters up include/core
with an 'uninteresting' utility class.
Change-Id: I7de9468500ecffd0b722f222932e4f8b6637925b
Reviewed-on: https://skia-review.googlesource.com/4522
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>