Add SkTypeface::makeClone.

This adds an method to typeface to allow users to create a copy of the
typeface with different arguments for its parameters. This is far more
efficient when animating a variation font.

BUG=skia:7121

Change-Id: I34e7557a08c7005f8149ea44f0c28de9c59d15a7
Reviewed-on: https://skia-review.googlesource.com/132480
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Mike Reed <reed@google.com>
2 files changed