Add special case circle blur for Ganesh

include/core/SkRRect.h

Index: include/core/SkRRect.h
diff --git a/include/core/SkRRect.h b/include/core/SkRRect.h
index 37766219df3a50f182c422da76c4c33826822523..68583d0654220b11db51d4e52e40b73c631e29e7 100644
--- a/include/core/SkRRect.h
+++ b/include/core/SkRRect.h
@@ -97,7 +97,10 @@ public:
     inline bool isOval() const { return kOval_Type == this->getType(); }
     inline bool isSimple() const { return kSimple_Type == this->getType(); }
     inline bool isSimpleCircular() const {
-        return this->isSimple() && fRadii[0].fX == fRadii[0].fY;
+        return this->isSimple() && SkScalarNearlyEqual(fRadii[0].fX, fRadii[0].fY);
+    }

[bsalomon, 2015/09/11 13:05:46]

I wonder if these should take a tolerance (just a thought). Thinking about cases
where matrix has a large scale factor but the rrect is in local space.

[robertphillips, 2015/09/11 15:55:35]

Done. I've added a todo. Right now I only use isCircle in device space.

+    inline bool isCircle() const {
+        return this->isOval() && SkScalarNearlyEqual(fRadii[0].fX, fRadii[0].fY);
     }
     inline bool isNinePatch() const { return kNinePatch_Type == this->getType(); }
     inline bool isComplex() const { return kComplex_Type == this->getType(); }
@@ -140,6 +143,12 @@ public:
         return rr;
     }
     
+    static SkRRect MakeOval(const SkRect& oval) {
+        SkRRect rr;
+        rr.setOval(oval);
+        return rr;
+    }
+
     /**
      * Set this RR to match the supplied oval. All x radii will equal half the
      * width and all y radii will equal half the height.