Enable the FocusController on DesktopAura too.

ui/views/corewm/corewm_switches.h

 // 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.
 
 #ifndef UI_VIEWS_COREWM_COREWM_SWITCHES_H_
 #define UI_VIEWS_COREWM_COREWM_SWITCHES_H_
 
 #include "build/build_config.h"
 #include "ui/views/views_export.h"
 
 namespace views {
 namespace corewm {
 namespace switches {
 
 // Note: If you add a switch, consider if it needs to be copied to a subsequent
 // command line if the process executes a new copy of itself.  (For example,
 // see chromeos::LoginUtil::GetOffTheRecordCommandLine().)
 
 // Please keep alphabetized.
 VIEWS_EXPORT extern const char kWindowAnimationsDisabled[];
 
 }  // namespace switches
 
 // Returns true if the new FocusController should be used as the
 // Activation/FocusClient.
 VIEWS_EXPORT bool UseFocusController();
 
+// Same as above but for Desktop mode.
+VIEWS_EXPORT bool UseFocusControllerOnDesktop();
+
 }  // namespace corewm
 }  // namespace views
 
 #endif  // UI_VIEWS_COREWM_COREWM_SWITCHES_H_