Update the window labels if they change in overview mode.

ui/aura/window.cc

Index: ui/aura/window.cc
diff --git a/ui/aura/window.cc b/ui/aura/window.cc
index 35b29245800305296a51d22587321b4717fb4bd8..455e7fb6a153ac8a4ecb7292fc299556f85ba875 100644
--- a/ui/aura/window.cc
+++ b/ui/aura/window.cc
@@ -305,6 +305,13 @@ void Window::SetName(const std::string& name) {
     UpdateLayerName();
 }
 
+void Window::SetTitle(const base::string16& title) {
+  title_ = title;
+  FOR_EACH_OBSERVER(WindowObserver,
+                    observers_,
+                    OnWindowTitleChanged(this, title));

[sky, 2014/06/25 16:24:44]

Callers that care about the title can ask for it. The only interesting thing
would be the old title, but since no one needs that either make
OnWindowTitleChanged only take the window.

[Nina, 2014/06/25 19:54:40]

Done. I was following the same logic as OnWindowParentChanged,
OnWindowVisibility*, OnWindowBoundsChanged and OnWindowRemovingFromRootWindow.
Perhaps we should also change those?

+}
+
 void Window::SetTransparent(bool transparent) {
   transparent_ = transparent;
   if (layer())