Update the window labels if they change in overview mode.

ash/wm/overview/window_selector_item.cc

Index: ash/wm/overview/window_selector_item.cc
diff --git a/ash/wm/overview/window_selector_item.cc b/ash/wm/overview/window_selector_item.cc
index 7b0d872a9462a88a69efe6caccffec70ff599741..56237eee49266f725a9d7a29539f2d4832610a41 100644
--- a/ash/wm/overview/window_selector_item.cc
+++ b/ash/wm/overview/window_selector_item.cc
@@ -141,7 +141,6 @@ void WindowSelectorItem::SetBounds(aura::Window* root_window,
   }
   activate_window_button_->SetBounds(target_bounds);
 
-  // TODO(nsatragno): Handle window title updates.
   UpdateWindowLabels(target_bounds, root_window, animate);
 
   gfx::Rect inset_bounds(target_bounds);
@@ -170,6 +169,12 @@ void WindowSelectorItem::ButtonPressed(views::Button* sender,
   views::Widget::GetWidgetForNativeView(SelectionWindow())->Close();
 }
 
+void WindowSelectorItem::OnWindowTitleChanged(aura::Window* window,
+                                              const base::string16& new_title) {
+  static_cast<views::Label*>(
+      window_label_->GetContentsView())->SetText(new_title);
+}
+
 void WindowSelectorItem::UpdateCloseButtonBounds(aura::Window* root_window,
                                                  bool animate) {
   gfx::RectF align_bounds(ScreenUtil::ConvertRectFromScreen(