Propagate window transformed notification to child hierarchy

ui/aura/window.cc

Index: ui/aura/window.cc
diff --git a/ui/aura/window.cc b/ui/aura/window.cc
index 5c05d4440acd1f96f612415f583f5fb75170b244..fb25f62a3d24ed8e984851e5454033187a7baeb1 100644
--- a/ui/aura/window.cc
+++ b/ui/aura/window.cc
@@ -409,6 +409,7 @@ void Window::SetTransform(const gfx::Transform& transform) {
   layer()->SetTransform(transform);
   FOR_EACH_OBSERVER(WindowObserver, observers_,
                     OnWindowTransformed(this));
+  NotifyAncestorWindowTransformed(this);
 }
 
 void Window::SetLayoutManager(LayoutManager* layout_manager) {
@@ -1317,6 +1318,15 @@ void Window::NotifyWindowVisibilityChangedUp(aura::Window* target,
   }
 }
 
+void Window::NotifyAncestorWindowTransformed(Window* source) {
+  FOR_EACH_OBSERVER(WindowObserver, observers_,
+                    OnAncestorWindowTransformed(source, this));
+  for (Window::Windows::const_iterator it = children_.begin();
+       it != children_.end(); ++it) {
+    (*it)->NotifyAncestorWindowTransformed(source);
+  }
+}
+
 void Window::OnWindowBoundsChanged(const gfx::Rect& old_bounds) {
   if (layer()) {
     bounds_ = layer()->bounds();