Hook up the FocusController behind a flag.

ash/wm/panel_layout_manager.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 "ash/wm/panel_layout_manager.h"
 
 #include <algorithm>
 #include <map>
 
 #include "ash/launcher/launcher.h"
@@ skipping 104 matching lines @@
     (*iter).x = std::max((*iter).min_x, std::min((*iter).max_x, x));
     x += delta;
   }
 }
 
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 // PanelLayoutManager public implementation:
 PanelLayoutManager::PanelLayoutManager(aura::Window* panel_container)
-    : panel_container_(panel_container),
+    : ActivationChangeShim(Shell::GetInstance()),
+      panel_container_(panel_container),
       in_layout_(false),
       dragged_panel_(NULL),
       launcher_(NULL),
       last_active_panel_(NULL),
       callout_widget_(new views::Widget),
       weak_factory_(this) {
   DCHECK(panel_container);
   views::Widget::InitParams params;
   params.type = views::Widget::InitParams::TYPE_POPUP;
   params.transparent = true;
@@ skipping 327 matching lines @@
   callout_bounds.set_x(
       icon_bounds.x() + (icon_bounds.width() - callout_bounds.width()) / 2);
   callout_bounds.set_y(bounds.bottom());
   SetChildBoundsDirect(callout_widget_->GetNativeWindow(), callout_bounds);
   panel_container_->StackChildAtTop(callout_widget_->GetNativeWindow());
   callout_widget_->Show();
 }
 
 }  // namespace internal
 }  // namespace ash