Move ActivationClient/Delegate to client namespace.

ui/aura/client/activation_client.cc

 // Copyright (c) 2011 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/client/activation_client.h"
 
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/root_window.h"
 
 namespace aura {
+namespace client {
 
-// static
-void ActivationClient::SetActivationClient(ActivationClient* client) {
+void SetActivationClient(ActivationClient* client) {
   RootWindow::GetInstance()->SetProperty(kRootWindowActivationClient, client);
 }
 
-// static
-ActivationClient* ActivationClient::GetActivationClient() {
+ActivationClient* GetActivationClient() {
   return reinterpret_cast<ActivationClient*>(
       RootWindow::GetInstance()->GetProperty(kRootWindowActivationClient));
 }
 
+}  // namespace client
 }  // namespace aura