hide paint's getFontBounds

Bug: skia:
Change-Id: I26b693e32d0dadfe47710a29296eceb8ec90ee0c
Reviewed-on: https://skia-review.googlesource.com/c/174308
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Herb Derby <herb@google.com>
8 files changed