Nukes aura::WindowDestructionObserver. It's effectively the same as

WindowTracker.

BUG=none
TEST=none
R=sadrul@chromium.org

Review URL: https://chromiumcodereview.appspot.com/22254003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@215821 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/renderer_host/render_widget_host_view_aura.cc

@@ -54,7 +54,6 @@
 #include "ui/aura/env.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window.h"
-#include "ui/aura/window_destruction_observer.h"
 #include "ui/aura/window_observer.h"
 #include "ui/aura/window_tracker.h"
 #include "ui/base/clipboard/scoped_clipboard_writer.h"
@@ -2481,12 +2480,13 @@ void RenderWidgetHostViewAura::OnKeyEvent(ui::KeyEvent* event) {
       aura::Window* host = *(host_tracker_->windows().begin());
       aura::client::FocusClient* client = aura::client::GetFocusClient(host);
       if (client) {
-        // Calling host->Focus() may delete |this|. We create a local
-        // observer for that. In that case we exit without further
-        // access to any members.
-        aura::WindowDestructionObserver destruction_observer(window_);
+        // Calling host->Focus() may delete |this|. We create a local observer
+        // for that. In that case we exit without further access to any members.
+        aura::WindowTracker tracker;
+        aura::Window* window = window_;
+        tracker.Add(window);
         host->Focus();
-        if (destruction_observer.destroyed()) {
+        if (!tracker.Contains(window)) {
           event->SetHandled();
           return;
         }

ui/aura/aura.gyp

@@ -101,8 +101,6 @@
         'window.cc',
         'window.h',
         'window_delegate.h',
-        'window_destruction_observer.cc',
-        'window_destruction_observer.h',
         'window_observer.h',
         'window_tracker.cc',
         'window_tracker.h',

ui/aura/window.cc

@@ -23,8 +23,8 @@
 #include "ui/aura/layout_manager.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window_delegate.h"
-#include "ui/aura/window_destruction_observer.h"
 #include "ui/aura/window_observer.h"
+#include "ui/aura/window_tracker.h"
 #include "ui/base/animation/multi_animation.h"
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/layer.h"
@@ -1027,13 +1027,14 @@ void Window::NotifyWindowVisibilityChanged(aura::Window* target,
 
 bool Window::NotifyWindowVisibilityChangedAtReceiver(aura::Window* target,
                                                      bool visible) {
-  // |this| may be deleted during a call to OnWindowVisibilityChanged
-  // on one of the observers. We create an local observer for that. In
-  // that case we exit without further access to any members.
-  WindowDestructionObserver destruction_observer(this);
+  // |this| may be deleted during a call to OnWindowVisibilityChanged() on one
+  // of the observers. We create an local observer for that. In that case we
+  // exit without further access to any members.
+  WindowTracker tracker;
+  tracker.Add(this);
   FOR_EACH_OBSERVER(WindowObserver, observers_,
                     OnWindowVisibilityChanged(target, visible));
-  return !destruction_observer.destroyed();
+  return tracker.Contains(this);
 }
 
 bool Window::NotifyWindowVisibilityChangedDown(aura::Window* target,

ui/aura/window_destruction_observer.cc

-// Copyright 2013 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_destruction_observer.h"
-
-namespace aura {
-
-WindowDestructionObserver::WindowDestructionObserver(Window* window)
-    : window_(window), destroyed_(false) {
-  DCHECK(window_);
-  window_->AddObserver(this);
-}
-
-WindowDestructionObserver::~WindowDestructionObserver() {
-  if (!destroyed_)
-    window_->RemoveObserver(this);
-}
-
-void WindowDestructionObserver::OnWindowDestroyed(Window* window) {
-  if (window == window_)
-    destroyed_ = true;
-}
-
-} // namespace aura

ui/aura/window_destruction_observer.h

-// Copyright 2013 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_DESTRUCTION_OBSERVER_H_
-#define UI_AURA_WINDOW_DESTRUCTION_OBSERVER_H_
-
-#include <set>
-
-#include "ui/aura/aura_export.h"
-#include "ui/aura/window.h"
-#include "ui/aura/window_observer.h"
-
-namespace aura {
-
-// A class for observing window (self) destruction. A side effect of a
-// window member funtion may be that the object, i.e. |this|, gets
-// deleted. This class can be used to detect such cases and to exit
-// the member function without any further access to member data. See
-// for example: aura::Window::NotifyWindowVisibilityChangedAtReceiver.
-
-class AURA_EXPORT WindowDestructionObserver : public WindowObserver {
- public:
-  // Addes this observer to window.
-  explicit WindowDestructionObserver(aura::Window* window);
-
-  // Removes this observer from |window_| unless |window_| has been
-  // observed to be destroyed.
-  virtual ~WindowDestructionObserver();
-
-  // Returns true if |window_| has been observed to be destroyed.
-  bool destroyed() const { return destroyed_; }
-
-  private:
-  // aura::WindowObserver overrides:
-  virtual void OnWindowDestroyed(Window* window) OVERRIDE;
-
-  Window* window_;
-  bool destroyed_;
-
-  DISALLOW_COPY_AND_ASSIGN(WindowDestructionObserver);
-};
-
-} // namespace aura
-
-#endif