[DRAFT] Create RenderFrameHostManager.

content/common/frame_messages.h

 // Copyright 2013 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 interacting with frames.
 // Multiply-included message file, hence no include guard.
 
 #include "content/common/content_export.h"
 #include "content/public/common/common_param_traits.h"
 #include "ipc/ipc_message_macros.h"
@@ skipping 67 matching lines @@
 // create a plugin.  The browser will create the plugin process if
 // necessary, and will return a handle to the channel on success.
 // On error an empty string is returned.
 IPC_SYNC_MESSAGE_CONTROL4_2(FrameHostMsg_OpenChannelToPlugin,
                             int /* render_frame_id */,
                             GURL /* url */,
                             GURL /* page_url */,
                             std::string /* mime_type */,
                             IPC::ChannelHandle /* channel_handle */,
                             content::WebPluginInfo /* info */)
+
+// Indicates that the current renderer has swapped out, after a SwapOut
+// message.
+IPC_MESSAGE_ROUTED0(FrameHostMsg_SwapOut_ACK)
+
+// Instructs the renderer to swap out for a cross-site transition, including
+// running the unload event handler. Expects a SwapOut_ACK message when
+// finished.
+IPC_MESSAGE_ROUTED0(FrameMsg_SwapOut)