Reland: add SkPath::shrinkToFit

Original CL: https://skia-review.googlesource.com/c/skia/+/150967

  * expanded tests
  * fixed shared pathref copying

Change-Id: I4bfe89f597485aa2db68f58d99112188615faceb
Reviewed-on: https://skia-review.googlesource.com/153553
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Mike Reed <reed@google.com>
Auto-Submit: Florin Malita <fmalita@chromium.org>
4 files changed