Eliminates all ash dependencies from WindowModalityController.

ui/aura/test/test_activation_client.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/test/test_activation_client.h"
 
 #include "ui/aura/client/activation_change_observer.h"
 #include "ui/aura/client/activation_delegate.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window.h"
@@ skipping 51 matching lines @@
   if (aura::client::GetActivationDelegate(window))
     aura::client::GetActivationDelegate(window)->OnLostActive();
 }
 
 Window* TestActivationClient::GetActiveWindow() {
   if (active_windows_.empty())
     return NULL;
   return active_windows_.back();
 }
 
+Window* TestActivationClient::GetActivatableWindow(Window* window) {
+  return NULL;
+}
+
 bool TestActivationClient::OnWillFocusWindow(Window* window,
                                              const ui::Event* event) {
   return true;
 }
 
 bool TestActivationClient::CanActivateWindow(Window* window) const {
   return true;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ skipping 17 matching lines @@
     if (active_windows_[i] == window) {
       active_windows_.erase(active_windows_.begin() + i);
       window->RemoveObserver(this);
       return;
     }
   }
 }
 
 }  // namespace test
 }  // namespace aura