Update the window labels if they change in overview mode.

ui/aura/window.cc

 // Copyright (c) 2012 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.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 287 matching lines @@
   type_ = type;
 }
 
 void Window::SetName(const std::string& name) {
   name_ = name;
 
   if (layer())
     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())
     layer()->SetFillsBoundsOpaquely(!transparent_);
 }
 
 void Window::SetFillsBoundsCompletely(bool fills_bounds) {
   if (layer())
     layer()->SetFillsBoundsCompletely(fills_bounds);
 }
@@ skipping 1114 matching lines @@
       return window;
     if (offset)
       *offset += window->bounds().OffsetFromOrigin();
   }
   if (offset)
     *offset = gfx::Vector2d();
   return NULL;
 }
 
 }  // namespace aura