New link rel=prerender api, using WebKit::WebPrerenderingPlatform

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 "googleurl/src/gurl.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_message_macros.h"
 #include "ipc/ipc_param_traits.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebReferrerPolicy.h"
+#include "ui/gfx/size.h"
 
 #define IPC_MESSAGE_START PrerenderMsgStart
 
+// Prerender Link Manager Messages

[mmenke, 2012/05/01 16:23:21]

nit:  PrerenderLinkManager

[gavinp, 2012/05/01 18:50:22]

Done.

+// These are messages sent from the renderer to the browser in
+// relation to <link rel=prerender> elements.
+
+// Notifies of the insertion of a <link rel=prerender> element in the
+// document.
+IPC_MESSAGE_CONTROL5(PrerenderHostMsg_AddPrerender,
+                     int /* id, assigned by WebPrerendererClient */,
+                     GURL /* url */,
+                     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_CancelPrerender,
+                     int /* id, assigned by WebPrerendererClient */)
+
+// Notifies on unloading a <link rel=prerender> element from a frame.
+IPC_MESSAGE_CONTROL1(PrerenderHostMsg_AbandonPrerender,
+                     int /* id, assigned by WebPrerendererClient */)
+
+// Prerender View Host Messages

[mmenke, 2012/05/01 16:23:21]

What is a Prerender View Host?  Generally (Like just above), messages are named
for who they're sent to, not who they're sent from, and "Host" objects are
generally in the browser process, but these are sent to the render process.

[gavinp, 2012/05/01 18:50:22]

Good point.  Renamed to PrerenderDispatcher Messages.

+// These are messages sent in relation to running prerenders.
+
 // Tells a renderer if it's currently being prerendered.  Must only be set
 // to true before any navigation occurs, and only set to false at most once
 // after that.
 IPC_MESSAGE_ROUTED1(PrerenderMsg_SetIsPrerendering,
                     bool /* whether the RenderView is prerendering */)
 
 // Specifies that a URL is currently being prerendered.
 IPC_MESSAGE_CONTROL1(PrerenderMsg_AddPrerenderURL,
                      GURL /* url */)
 
 // Specifies that a URL is no longer being prerendered.
 IPC_MESSAGE_CONTROL1(PrerenderMsg_RemovePrerenderURL,
                      GURL /* url */)