aura: Remove layerless windows.

ui/aura/window.h

 // 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.
 
 #ifndef UI_AURA_WINDOW_H_
 #define UI_AURA_WINDOW_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "base/strings/string16.h"
 #include "ui/aura/aura_export.h"
-#include "ui/aura/window_layer_type.h"
 #include "ui/aura/window_observer.h"
 #include "ui/compositor/layer_animator.h"
 #include "ui/compositor/layer_delegate.h"
 #include "ui/compositor/layer_owner.h"
 #include "ui/events/event_constants.h"
 #include "ui/events/event_target.h"
 #include "ui/events/event_targeter.h"
 #include "ui/events/gestures/gesture_types.h"
 #include "ui/gfx/geometry/insets.h"
 #include "ui/gfx/geometry/rect.h"
@@ skipping 45 matching lines @@
     STACK_ABOVE,
     STACK_BELOW
   };
 
   typedef std::vector<Window*> Windows;
 
   explicit Window(WindowDelegate* delegate);
   ~Window() override;
 
   // Initializes the window. This creates the window's layer.
-  void Init(WindowLayerType layer_type);
+  void Init(ui::LayerType layer_type);
 
   void set_owned_by_parent(bool owned_by_parent) {
     owned_by_parent_ = owned_by_parent;
   }
   bool owned_by_parent() const { return owned_by_parent_; }
 
   // A type is used to identify a class of Windows and customize behavior such
   // as event handling and parenting.  This field should only be consumed by the
   // shell -- Aura itself shouldn't contain type-specific logic.
   ui::wm::WindowType type() const { return type_; }
@@ skipping 451 matching lines @@
   };
 
   std::map<const void*, Value> prop_map_;
 
   DISALLOW_COPY_AND_ASSIGN(Window);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_WINDOW_H_