[mus+ash] Removes WmWindow from ash/wm/window_cycle_*

ash/wm_window.cc

Index: ash/wm_window.cc
diff --git a/ash/wm_window.cc b/ash/wm_window.cc
index 2365c6399b8fbb840067058ef2fc701ba4bf7f90..afb587810e96206da8ac02b22e0113042422f7b8 100644
--- a/ash/wm_window.cc
+++ b/ash/wm_window.cc
@@ -14,7 +14,6 @@
 #include "ash/wm/resize_shadow_controller.h"
 #include "ash/wm/widget_finder.h"
 #include "ash/wm/window_animations.h"
-#include "ash/wm/window_mirror_view.h"
 #include "ash/wm/window_properties.h"
 #include "ash/wm/window_state.h"
 #include "ash/wm/window_state_aura.h"
@@ -672,10 +671,6 @@ void WmWindow::SetChildrenUseExtendedHitRegion() {
       window_, mouse_extend, touch_extend));
 }
 
-std::unique_ptr<views::View> WmWindow::CreateViewWithRecreatedLayers() {
-  return base::MakeUnique<wm::WindowMirrorView>(this);
-}
-
 void WmWindow::AddTransientWindowObserver(WmTransientWindowObserver* observer) {
   if (!added_transient_observer_) {
     added_transient_observer_ = true;