GuestView: Fix message routing across embedder navigations

extensions/common/guest_view/guest_view_messages.h

 // Copyright 2015 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.
 
 // IPC messages for GuestViews.
 // Multiply-included message file, hence no include guard.
 
 #include <string>
 
 #include "base/values.h"
@@ skipping 24 matching lines @@
 // |element_instance_id| from a GuestViewBase if it is attached to one.
 // In other words, routing of input and graphics will no longer flow through
 // the container associated with the provided ID.
 IPC_MESSAGE_CONTROL1(GuestViewMsg_GuestDetached,
                      int /* element_instance_id*/)
 
 // Messages sent from the renderer to the browser.
 
 // Sent by the renderer to set initialization parameters of a Browser Plugin
 // that is identified by |element_instance_id|.
-IPC_MESSAGE_CONTROL4(GuestViewHostMsg_AttachGuest,
-                     int /* routing_id */,
+IPC_MESSAGE_CONTROL3(GuestViewHostMsg_AttachGuest,
                      int /* element_instance_id */,
                      int /* guest_instance_id */,
                      base::DictionaryValue /* attach_params */)
 
 // Tells the browser to create a mime handler guest view for a plugin.
 IPC_MESSAGE_CONTROL4(GuestViewHostMsg_CreateMimeHandlerViewGuest,
                      int /* render_frame_id */,
                      std::string /* view_id */,
                      int /* element_instance_id */,
                      gfx::Size /* element_size */)