Make GrConvexPolyEffect support inverse fills and non-AA rects

BUG=skia:2151
R=robertphillips@google.com

Author: bsalomon@google.com

Review URL: https://codereview.chromium.org/183833003

git-svn-id: http://skia.googlecode.com/svn/trunk@13621 2bbb7eff-a529-9590-31e7-b0007b416f81
4 files changed