Move PageTransition into content namespace. While I'm touching all these files, I've also updated...

content/test/render_view_fake_resources_test.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 "content/test/render_view_fake_resources_test.h"
 
 #include <string.h>
 
 #include "base/process.h"
 #include "base/shared_memory.h"
@@ skipping 180 matching lines @@
     const WebKit::WebHistoryItem& history_item) {
   RenderViewImpl* impl = static_cast<RenderViewImpl*>(view_);
   ViewMsg_Navigate_Params params;
   params.page_id = impl->GetPageId() + offset;
   params.pending_history_list_offset =
       impl->history_list_offset() + offset;
   params.current_history_list_offset = impl->history_list_offset();
   params.current_history_list_length = (impl->historyBackListCount() +
                                         impl->historyForwardListCount() + 1);
   params.url = GURL(history_item.urlString());
-  params.transition = PageTransition::FORWARD_BACK;
+  params.transition = content::PAGE_TRANSITION_FORWARD_BACK;
   params.state = webkit_glue::HistoryItemToString(history_item);
   params.navigation_type = ViewMsg_Navigate_Type::NORMAL;
   params.request_time = base::Time::Now();
   channel_->Send(new ViewMsg_Navigate(impl->routing_id(), params));
   message_loop_.Run();
 }