Initial implementation of a SkColorSpace_A2B xform

src/core/SkColorSpace_A2B.h

Index: src/core/SkColorSpace_A2B.h
diff --git a/src/core/SkColorSpace_A2B.h b/src/core/SkColorSpace_A2B.h
index 726e3d7fdd308adf7a03c42b299daa11857a6d7f..2fb7a83cabc7162f7b51ade9de02c0cd4b67c7e5 100644
--- a/src/core/SkColorSpace_A2B.h
+++ b/src/core/SkColorSpace_A2B.h
@@ -132,7 +132,7 @@ public:
     };
     const Element& element(size_t i) const { return fElements[i]; }
     
-    size_t count() const { return fElements.size(); }
+    int count() const { return (int)fElements.size(); }
 
     // the intermediate profile connection space that this color space
     // represents the transformation to
@@ -150,6 +150,7 @@ private:
     std::vector<Element> fElements;
 
     friend class SkColorSpace;
+    friend class ColorSpaceXformTest;
     typedef SkColorSpace_Base INHERITED;
 };