Refactors DimWindow and moves to ash/common

ash/aura/wm_window_aura.cc

Index: ash/aura/wm_window_aura.cc
diff --git a/ash/aura/wm_window_aura.cc b/ash/aura/wm_window_aura.cc
index f923414d7fe790cb5b17b0c18d99b55e00e06b5e..bf4a8577c50e9887a94175af843d82b8dfcb5cbd 100644
--- a/ash/aura/wm_window_aura.cc
+++ b/ash/aura/wm_window_aura.cc
@@ -96,6 +96,8 @@ WmWindowAura::~WmWindowAura() {
     ::wm::TransientWindowManager::Get(window_)->RemoveObserver(this);
 
   window_->RemoveObserver(this);
+
+  DestroyUserData();
 }
 
 // static
@@ -135,6 +137,10 @@ const aura::Window* WmWindowAura::GetAuraWindow(const WmWindow* wm_window) {
                    : nullptr;
 }
 
+void WmWindowAura::Destroy() {
+  delete window_;
+}
+
 const WmWindow* WmWindowAura::GetRootWindow() const {
   return Get(window_->GetRootWindow());
 }
@@ -365,6 +371,10 @@ WmLayoutManager* WmWindowAura::GetLayoutManager() {
   return adapter ? adapter->wm_layout_manager() : nullptr;
 }
 
+void WmWindowAura::SetVisibilityChangesAnimated() {
+  ::wm::SetWindowVisibilityChangesAnimated(window_);
+}
+
 void WmWindowAura::SetVisibilityAnimationType(int type) {
   ::wm::SetWindowVisibilityAnimationType(window_, type);
 }