Revert 239232 "Make sure WindowObservers are removed from window..."

> Make sure WindowObservers are removed from window before destruction
> 
> * Check if the window observer is empty upon destruction.
> * remove the all observers in ~WindowObserver()
> * Remove RemoveObserver that are no longer necessary
> * Fix shell shutdown order so that observers are removed correctly before deleting all windows.
> 
> BUG=324018
> R=skuhne@chromium.org, sky@chromium.org
> 
> Review URL: https://codereview.chromium.org/101013002

TBR=oshima@chromium.org

Review URL: https://codereview.chromium.org/103863003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239239 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 5 insertions, 15 deletions

diff --git a/ui/aura/client/default_activation_client.cc b/ui/aura/client/default_activation_client.cc
index ccb660b..629f12a 100644
--- a/ui/aura/client/default_activation_client.cc
+++ b/ui/aura/client/default_activation_client.cc
@@ -102,6 +102,7 @@ void DefaultActivationClient::OnWindowDestroyed(Window* window) {
     last_active_ = NULL;
 
   if (window == GetActiveWindow()) {
+    window->RemoveObserver(this);
     active_windows_.pop_back();
     Window* next_active = GetActiveWindow();
     if (next_active && aura::client::GetActivationChangeObserver(next_active)) {
diff --git a/ui/aura/window.cc b/ui/aura/window.cc
index 2655b8a..692e345 100644
--- a/ui/aura/window.cc
+++ b/ui/aura/window.cc
@@ -168,12 +168,7 @@ Window::~Window() {
   // Delegate and observers need to be notified after transients are deleted.
   if (delegate_)
     delegate_->OnWindowDestroyed();
-  ObserverListBase<WindowObserver>::Iterator iter(observers_);
-  WindowObserver* observer;
-  while ((observer = iter.GetNext())) {
-    RemoveObserver(observer);
-    observer->OnWindowDestroyed(this);
-  }
+  FOR_EACH_OBSERVER(WindowObserver, observers_, OnWindowDestroyed(this));
 
   // Clear properties.
   for (std::map<const void*, Value>::const_iterator iter = prop_map_.begin();
diff --git a/ui/aura/window.h b/ui/aura/window.h
index c6dcd09..f2a5672 100644
--- a/ui/aura/window.h
+++ b/ui/aura/window.h
@@ -588,7 +588,7 @@ class AURA_EXPORT Window : public ui::LayerDelegate,
   gfx::Insets hit_test_bounds_override_outer_touch_;
   gfx::Insets hit_test_bounds_override_inner_;
 
-  ObserverList<WindowObserver, true> observers_;
+  ObserverList<WindowObserver> observers_;
 
   // Value struct to keep the name and deallocator for this property.
   // Key cannot be used for this purpose because it can be char* or
diff --git a/ui/aura/window_observer.h b/ui/aura/window_observer.h
index 9408ee8..5008ac5 100644
--- a/ui/aura/window_observer.h
+++ b/ui/aura/window_observer.h
@@ -87,14 +87,8 @@ class AURA_EXPORT WindowObserver {
   // destructor). This is called before the window is removed from its parent.
   virtual void OnWindowDestroying(Window* window) {}
 
-  // Invoked when the Window has been destroyed (i.e. at the end of
-  // its destructor). This is called after the window is removed from
-  // its parent.  Window automatically removes its WindowObservers
-  // before calling this method, so the following code is no op.
-  //
-  // void MyWindowObserver::OnWindowDestroyed(aura::Window* window) {
-  //    window->RemoveObserver(this);
-  // }
+  // Invoked when the Window has been destroyed (i.e. at the end of its
+  // destructor). This is called after the window is removed from its parent.
   virtual void OnWindowDestroyed(Window* window) {}
 
   // Called when a Window has been added to a RootWindow.