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

ash/test/mirror_window_test_api.cc

Index: ash/test/mirror_window_test_api.cc
diff --git a/ash/test/mirror_window_test_api.cc b/ash/test/mirror_window_test_api.cc
index cd1926a43dd1a6516240e41c764b477abdb64d2c..30e5624d64ab07b6a7d28c22093353c19d00a8ca 100644
--- a/ash/test/mirror_window_test_api.cc
+++ b/ash/test/mirror_window_test_api.cc
@@ -32,6 +32,11 @@ const gfx::Point& MirrorWindowTestApi::GetCursorHotPoint() const {
       cursor_window_controller()->hot_point_;
 }
 
+gfx::Point MirrorWindowTestApi::GetCursorHotPointLocationInRootWindow() const {
+  return GetCursorWindow()->GetBoundsInRootWindow().origin() +
+         GetCursorHotPoint().OffsetFromOrigin();
+}
+
 const aura::Window* MirrorWindowTestApi::GetCursorWindow() const {
   return Shell::GetInstance()->display_controller()->
       cursor_window_controller()->cursor_window_.get();