Fix SkPaint::getTypeface() documentation.

SkPaint::getTypeface() allows the caller to borrow a pointer to its
SkTypeface, it does not affect ownership. The existing documentation would
lead a user to beleive that getTypeface() increments the reference count,
but it does not.

TBR=reed@google.com
Change-Id: Ic1a660b026e3c4295f9f0de28abfde29c3f05524
Reviewed-on: https://skia-review.googlesource.com/137183
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>
2 files changed