aura: Some changes in Window and Desktop.

ui/aura/window.cc

Index: ui/aura/window.cc
diff --git a/ui/aura/window.cc b/ui/aura/window.cc
index 07c48e64fc089fbc2a43102b87cbb791ca4dba68..95c93cb257a71c869445cc2ed0f851c5a898dc78 100644
--- a/ui/aura/window.cc
+++ b/ui/aura/window.cc
@@ -35,6 +35,8 @@ Window::Window(WindowDelegate* delegate)
 }
 
 Window::~Window() {
+  FOR_EACH_OBSERVER(Observer, observers_, OnWindowClosing(this));
+
   // Let the delegate know we're in the processing of destroying.
   if (delegate_)
     delegate_->OnWindowDestroying();
@@ -114,10 +116,14 @@ void Window::Restore() {
 void Window::Activate() {
   // If we support minimization need to ensure this restores the window first.
   aura::Desktop::GetInstance()->SetActiveWindow(this, this);
+  FOR_EACH_OBSERVER(Observer, observers_,
+                    OnWindowActivationChanged(this, true));
 }
 
 void Window::Deactivate() {
   aura::Desktop::GetInstance()->Deactivate(this);
+  FOR_EACH_OBSERVER(Observer, observers_,
+                    OnWindowActivationChanged(this, false));
 }
 
 bool Window::IsActive() const {
@@ -259,6 +265,18 @@ bool Window::OnKeyEvent(KeyEvent* event) {
   return IsVisible() && delegate_->OnKeyEvent(event);
 }
 
+void Window::AddObserver(Window::Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void Window::RemoveObserver(Window::Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+bool Window::HasObserver(Window::Observer* observer) {
+  return observers_.HasObserver(observer);
+}
+
 bool Window::HitTest(const gfx::Point& point) {
   gfx::Rect local_bounds(gfx::Point(), bounds().size());
   // TODO(beng): hittest masks.
@@ -371,6 +389,9 @@ void Window::SetVisible(bool visible) {
     if (delegate_)
       delegate_->OnWindowVisibilityChanged(is_visible);
   }
+
+  FOR_EACH_OBSERVER(Observer, observers_,
+                    OnWindowVisibilityChanged(this, visible));
 }
 
 void Window::SchedulePaint() {