Moves MruWindowTracker into common

ash/wm/window_cycle_list.cc

 // Copyright 2014 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 "ash/wm/window_cycle_list.h"
 
+#include "ash/common/wm/mru_window_tracker.h"
 #include "ash/common/wm/window_state.h"
 #include "ash/common/wm_window.h"
 #include "ash/shell.h"
-#include "ash/wm/mru_window_tracker.h"
 #include "ash/wm/window_animations.h"
 #include "ash/wm/window_util.h"
 
 namespace ash {
 
 // Returns the window immediately below |window| in the current container.
 WmWindow* GetWindowBelow(WmWindow* window) {
   WmWindow* parent = window->GetParent();
   if (!parent)
     return nullptr;
@@ skipping 139 matching lines @@
   CHECK(i != windows_.end());
   int removed_index = static_cast<int>(i - windows_.begin());
   windows_.erase(i);
   if (current_index_ > removed_index ||
       current_index_ == static_cast<int>(windows_.size())) {
     current_index_--;
   }
 }
 
 }  // namespace ash