Add getReducedClipStack to lua canvas

include/utils/SkLua.h

Index: include/utils/SkLua.h
diff --git a/include/utils/SkLua.h b/include/utils/SkLua.h
index f67502a2e83a0033ada6041b31f7337b8ee9549c..2f29343d595c4f863245ad0591e84297e058dddf 100644
--- a/include/utils/SkLua.h
+++ b/include/utils/SkLua.h
@@ -8,6 +8,7 @@
 #ifndef SkLua_DEFINED
 #define SkLua_DEFINED
 
+#include "SkClipStack.h"
 #include "SkColor.h"
 #include "SkScalar.h"
 #include "SkString.h"
@@ -15,7 +16,6 @@
 struct lua_State;
 
 class SkCanvas;
-class SkClipStack;
 class SkMatrix;
 class SkPaint;
 class SkPath;
@@ -55,6 +55,10 @@ public:
     void pushPath(const SkPath&, const char tableKey[] = NULL);
     void pushCanvas(SkCanvas*, const char tableKey[] = NULL);
     void pushClipStack(const SkClipStack&, const char tableKey[] = NULL);
+    void pushClipStackElement(const SkClipStack::Element& element, const char tableKey[] = NULL);
+
+    // This SkCanvas lua methods is declared here to benefit from SkLua's friendship with SkCanvas.
+    static int lcanvas_getReducedClipStack(lua_State* L);
 
 private:
     lua_State*  fL;