[Prerender] Change IPC from bool to enum for more prerender modes

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 <stdint.h>
 
+#include "chrome/common/prerender_types.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 "ui/gfx/geometry/size.h"
 #include "url/gurl.h"
 #include "url/ipc/url_param_traits.h"
 
 #define IPC_MESSAGE_START PrerenderMsgStart
 
+IPC_ENUM_TRAITS_MAX_VALUE(prerender::PrerenderMode,
+                          prerender::PRERENDER_MODE_COUNT - 1)
+
 // 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_t, rel_types)
 IPC_STRUCT_END()
 
 // Notifies of the insertion of a <link rel=prerender> element in the
@@ skipping 11 matching lines @@
 
 // Notifies on unloading a <link rel=prerender> element from a frame.
 IPC_MESSAGE_CONTROL1(PrerenderHostMsg_AbandonLinkRelPrerender,
                      int /* prerender_id, assigned by WebPrerendererClient */)
 
 // PrerenderDispatcher Messages
 // These are messages sent from the browser to the renderer 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 */)
+// before any navigation occurs, and only set to NO_PRERENDER at most once after
+// that.
+IPC_MESSAGE_ROUTED1(PrerenderMsg_SetIsPrerendering, prerender::PrerenderMode)
 
 // Signals to launcher that a prerender is running.
 IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderStart,
                      int /* prerender_id */)
 
 // Signals to launcher that a prerender is running.
 IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderStopLoading,
                      int /* prerender_id */)
 
 // Signals to launcher that a prerender has had it's 'domcontentloaded' event.
 IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderDomContentLoaded,
                      int /* prerender_id */)
 
 // Signals to a launcher that a new alias has been added to a prerender.
 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 */)