Generalize layer mirroring for phantom windows

ui/aura/window.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/aura/window.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
@@ skipping 125 matching lines @@
   // acquired it.
   layer()->set_delegate(NULL);
   DestroyLayer();
 }
 
 void Window::Init(ui::LayerType layer_type) {
   if (!port_owner_) {
     port_owner_ = Env::GetInstance()->CreateWindowPort(this);
     port_ = port_owner_.get();
   }
-  SetLayer(new ui::Layer(layer_type));
+  SetLayer(base::MakeUnique<ui::Layer>(layer_type));
   std::unique_ptr<WindowPortInitData> init_data = port_->OnPreInit(this);
   layer()->SetVisible(false);
   layer()->set_delegate(this);
   UpdateLayerName();
   layer()->SetFillsBoundsOpaquely(!transparent_);
   Env::GetInstance()->NotifyWindowInitialized(this);
   port_->OnPostInit(std::move(init_data));
 }
 
 void Window::SetType(ui::wm::WindowType type) {
@@ skipping 947 matching lines @@
     layer_name = "Unnamed Window";
 
   if (id_ != -1)
     layer_name += " " + base::IntToString(id_);
 
   layer()->set_name(layer_name);
 #endif
 }
 
 }  // namespace aura