Converts MaximizeModeWindowManager to use ash/common types

ash/aura/wm_window_aura.cc

 // Copyright 2016 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 "ash/aura/wm_window_aura.h"
 
 #include "ash/aura/aura_layout_manager_adapter.h"
 #include "ash/aura/wm_root_window_controller_aura.h"
 #include "ash/aura/wm_shell_aura.h"
 #include "ash/common/ash_constants.h"
@@ skipping 68 matching lines @@
 }  // namespace
 
 WmWindowAura::WmWindowAura(aura::Window* window)
     : window_(window),
       // Mirrors that of aura::Window.
       observers_(base::ObserverList<WmWindowObserver>::NOTIFY_EXISTING_ONLY) {
   window_->AddObserver(this);
   window_->SetProperty(kWmWindowKey, this);
 }
 
+WmWindowAura::~WmWindowAura() {
+  window_->RemoveObserver(this);
+}
+
 // static
 const WmWindow* WmWindowAura::Get(const aura::Window* window) {
   if (!window)
     return nullptr;
 
   const WmWindow* wm_window = window->GetProperty(kWmWindowKey);
   if (wm_window)
     return wm_window;
   // WmWindowAura is owned by the aura::Window.
   // TODO(sky): fix constness.
@@ skipping 533 matching lines @@
 }
 
 void WmWindowAura::AddObserver(WmWindowObserver* observer) {
   observers_.AddObserver(observer);
 }
 
 void WmWindowAura::RemoveObserver(WmWindowObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
-WmWindowAura::~WmWindowAura() {
-  window_->RemoveObserver(this);
+bool WmWindowAura::HasObserver(const WmWindowObserver* observer) const {
+  return observers_.HasObserver(observer);
 }
 
 void WmWindowAura::OnWindowHierarchyChanging(
     const HierarchyChangeParams& params) {
   WmWindowObserver::TreeChangeParams wm_params;
   wm_params.target = Get(params.target);
   wm_params.new_parent = Get(params.new_parent);
   wm_params.old_parent = Get(params.old_parent);
   FOR_EACH_OBSERVER(WmWindowObserver, observers_,
                     OnWindowTreeChanging(this, wm_params));
@@ skipping 58 matching lines @@
                                               bool visible) {
   FOR_EACH_OBSERVER(WmWindowObserver, observers_,
                     OnWindowVisibilityChanging(this, visible));
 }
 
 void WmWindowAura::OnWindowTitleChanged(aura::Window* window) {
   FOR_EACH_OBSERVER(WmWindowObserver, observers_, OnWindowTitleChanged(this));
 }
 
 }  // namespace ash