Add support for circular gradients to the GL renderer.

This change also adds full support for local transformation matrices on
sweep and radial gradients.

Change-Id: Id8773bc0766575190e3f3d51984fc5e57b266c3f
diff --git a/libs/hwui/Matrix.h b/libs/hwui/Matrix.h
index c247a67..0608efe 100644
--- a/libs/hwui/Matrix.h
+++ b/libs/hwui/Matrix.h
@@ -83,6 +83,8 @@
         load(u);
     }
 
+    void multiply(float v);
+
     void translate(float x, float y, float z) {
         Matrix4 u;
         u.loadTranslate(x, y, z);