Add <link rel=next> support to prerender.

chrome/common/prerender_messages.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.
 
 // Multiply-included message file, no traditional include guard.
 #include "content/public/common/common_param_traits.h"
 #include "content/public/common/referrer.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_message_macros.h"
 #include "ipc/ipc_param_traits.h"
 #include "third_party/WebKit/public/platform/WebReferrerPolicy.h"
 #include "ui/gfx/size.h"
 #include "url/gurl.h"
 
 #define IPC_MESSAGE_START PrerenderMsgStart
 
 // PrerenderLinkManager Messages
 // These are messages sent from the renderer to the browser in
 // relation to <link rel=prerender> elements.
 
+IPC_STRUCT_BEGIN(PrerenderAttributes)
+  IPC_STRUCT_MEMBER(GURL, url)
+  IPC_STRUCT_MEMBER(uint32, rel_types)
+IPC_STRUCT_END()
+
 // Notifies of the insertion of a <link rel=prerender> element in the
 // document.
 IPC_MESSAGE_CONTROL5(PrerenderHostMsg_AddLinkRelPrerender,
                      int /* prerender_id, assigned by WebPrerendererClient */,
-                     GURL /* url */,
+                     PrerenderAttributes,
                      content::Referrer,
                      gfx::Size,
                      int /* render_view_route_id of launcher */)
 
 // Notifies on removal of a <link rel=prerender> element from the document.
 IPC_MESSAGE_CONTROL1(PrerenderHostMsg_CancelLinkRelPrerender,
                      int /* prerender_id, assigned by WebPrerendererClient */)
 
 // Notifies on unloading a <link rel=prerender> element from a frame.
 IPC_MESSAGE_CONTROL1(PrerenderHostMsg_AbandonLinkRelPrerender,
@@ skipping 21 matching lines @@
 IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderAddAlias,
                      GURL /* url */)
 
 // Signals to a launcher that a new alias has been added to a prerender.
 IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderRemoveAliases,
                      std::vector<GURL> /* urls */)
 
 // Signals to a launcher that a prerender is no longer running.
 IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderStop,
                      int /* prerender_id */)