Add a lock screen example.

ui/aura/root_window.cc

 // Copyright (c) 2011 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/root_window.h"
 
 #include "base/logging.h"
 #include "base/utf_string_conversions.h"
 #include "ui/aura/desktop.h"
 #include "ui/aura/event.h"
@@ skipping 39 matching lines @@
     MouseEvent translated_event(event, this, target);
     return target->OnMouseEvent(&translated_event);
   }
   return false;
 }
 
 bool RootWindow::HandleKeyEvent(const KeyEvent& event) {
   Window* focused_window = GetFocusManager()->focused_window();
   if (focused_window) {
     KeyEvent translated_event(event);
-    return GetFocusManager()->focused_window()->OnKeyEvent(&translated_event);
+    return focused_window->OnKeyEvent(&translated_event);
   }
   return false;
 }
 
 void RootWindow::SetCapture(Window* window) {
   if (capture_window_ == window)
     return;
 
   if (capture_window_ && capture_window_->delegate())
     capture_window_->delegate()->OnCaptureLost();
@@ skipping 56 matching lines @@
   // Send an entered event.
   if (mouse_moved_handler_ && mouse_moved_handler_->delegate()) {
     MouseEvent translated_event(event, this, mouse_moved_handler_,
                                 ui::ET_MOUSE_ENTERED);
     mouse_moved_handler_->OnMouseEvent(&translated_event);
   }
 }
 
 }  // namespace internal
 }  // namespace aura