Fix the content_browsertests everywhere maybe.

ash/shell.h

Index: ash/shell.h
diff --git a/ash/shell.h b/ash/shell.h
index 014029b36c00cfb34946f61b92261199df71ce32..a9cdcd2abd1f0c9d4063946217bf34f5c390370a 100644
--- a/ash/shell.h
+++ b/ash/shell.h
@@ -33,7 +33,6 @@ class Window;
 namespace client {
 class ActivationClient;
 class FocusClient;
-class StackingClient;
 class UserActionClient;
 }
 }
@@ -432,8 +431,6 @@ class ASH_EXPORT Shell
   }
 #endif  // defined(OS_CHROMEOS)
 
- aura::client::StackingClient* stacking_client();
-
  RootWindowHostFactory* root_window_host_factory() {
    return root_window_host_factory_.get();
  }
@@ -514,7 +511,6 @@ class ASH_EXPORT Shell
 
   scoped_ptr<internal::AppListController> app_list_controller_;
 
-  scoped_ptr<aura::client::StackingClient> stacking_client_;
   scoped_ptr<internal::ActivationController> activation_controller_;
   scoped_ptr<internal::CaptureController> capture_controller_;
   scoped_ptr<internal::DragDropController> drag_drop_controller_;