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.

Change-Id: Ie41a5b76bef8eaf05b56b65774eaf38aad0dc4cf
Reviewed-on: https://skia-review.googlesource.com/132934
Commit-Queue: Bruce Wang <brucewang@google.com>
Reviewed-by: Bruce Wang <brucewang@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
3 files changed