Add more tests for mouse rotation,scale&position after display change

ash/test/mirror_window_test_api.h

Index: ash/test/mirror_window_test_api.h
diff --git a/ash/test/mirror_window_test_api.h b/ash/test/mirror_window_test_api.h
index ce58f971b5fd52214297a418e9c513ae9adbd525..ef7fcfbb4c61d3f3560d633dc8df40e140c640dc 100644
--- a/ash/test/mirror_window_test_api.h
+++ b/ash/test/mirror_window_test_api.h
@@ -30,7 +30,15 @@ class MirrorWindowTestApi {
   const aura::WindowTreeHost* GetHost() const;
 
   int GetCurrentCursorType() const;
+
+  // Returns the position of the hot point within the cursor. This is
+  // unaffected by the cursor location.
   const gfx::Point& GetCursorHotPoint() const;
+
+  // Returns the position of the cursor hot point in root window coordinates.
+  // This should be the same as the native cursor location.
+  gfx::Point GetCursorHotPointLocationInRootWindow() const;
+
   const aura::Window* GetCursorWindow() const;
 
   scoped_ptr<RootWindowTransformer> CreateCurrentRootWindowTransformer() const;