Add a GrShape::Type value for an inverted empty path

Change-Id: Ib34a608db07a2ff1d7bdfbd96867fa5ff0ac9782
Reviewed-on: https://skia-review.googlesource.com/41540
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
3 files changed