Improve handling of inverse clip paths in GrClipMaskManager.

Will require rebaselining of complexclip_aa and complexclip_aa_layer on GPU.

R=robertphillips@google.com
Review URL: https://codereview.appspot.com/6907052

git-svn-id: http://skia.googlecode.com/svn/trunk@6712 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/core/SkClipStack.h b/include/core/SkClipStack.h
index 6af60a2..52b1b22 100644
--- a/include/core/SkClipStack.h
+++ b/include/core/SkClipStack.h
@@ -98,6 +98,10 @@
             when it is rasterized. */
         bool isAA() const { return fDoAA; }
 
+        //!< Inverts the fill of the clip shape. Note that a kEmpty element remains kEmpty.
+        void invertShapeFillType();
+
+        //!< Sets the set operation represented by the element.
         void setOp(SkRegion::Op op) { fOp = op; }
 
         /** The GenID can be used by clip stack clients to cache representations of the clip. The