Add PrerenderStatusEvent on Prerenders

chrome/renderer/prerender/prerender_dispatcher.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.
 
 #ifndef CHROME_RENDERER_PRERENDER_PRERENDER_DISPATCHER_H_
 #define CHROME_RENDERER_PRERENDER_PRERENDER_DISPATCHER_H_
 
 #include <map>
+#include <set>
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/public/renderer/render_process_observer.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebPrerenderingSupport.h"
 
 class GURL;
 
 namespace prerender {
 
-class PrerenderingSupport;
+// There is one PrerenderDispatcher per render process. It keeps track of
+// prerenders launched by WebKit, and signals the browser process. It tracks
+// prerenders have been launched, and sends events on lifetime events to
+// WebKit.
+// TODO(gavinp): Add more syncronization between the WebKit origin data and the
+// browser process origin data.
 
-// PrerenderDispatcher keeps track of which URLs are being prerendered. There
-// is only one PrerenderDispatcher per render process, and it will only be
-// aware of prerenders that are triggered by this render process.  As well,
-// it holds on to other objects that must exist once per-renderer process,
-// such as the PrerenderingSupport.
-class PrerenderDispatcher : public content::RenderProcessObserver {
+class PrerenderDispatcher : public content::RenderProcessObserver,
+                            public WebKit::WebPrerenderingSupport {
  public:
   PrerenderDispatcher();
   virtual ~PrerenderDispatcher();
 
   bool IsPrerenderURL(const GURL & url) const;
 
  private:
   friend class PrerenderDispatcherTest;
 
-  void OnAddPrerenderURL(const GURL& url);
-  void OnRemovePrerenderURL(const GURL& url);
+  // Message handlers for messages from the browser process.
+  void OnStartedPrerender(int prerender_id);
+  void OnAddAliasToPrerender(int prerender_id, const GURL& url);
+  void OnStoppedPrerender(int prerender_id);
 
-  // RenderProcessObserver:
+  // from RenderProcessObserver
   virtual bool OnControlMessageReceived(const IPC::Message& message) OVERRIDE;
 
-  typedef std::map<GURL, int> PrerenderMap;
-  PrerenderMap prerender_urls_;
+  // from WebKit::WebPrerenderingSupport
+  virtual void add(WebKit::WebPrerender* prerender) OVERRIDE;
+  virtual void cancel(WebKit::WebPrerender* prerender) OVERRIDE;
+  virtual void abandon(WebKit::WebPrerender* prerender) OVERRIDE;
 
-  // There is one PrerenderingSupport object per renderer, and it provides
-  // the interface to prerendering to the WebKit platform.
-  scoped_ptr<PrerenderingSupport> prerendering_support_;
+  // from WebKit, prerender elements launched by renderers in our process.
+  std::map<int, WebKit::WebPrerender*> prerenders_;
+
+  // from the browser process, which prerenders have been launched.

[mmenke, 2012/09/12 16:31:45]

nit:  Comments are generally capitalized (And those ending in periods should
always be capitalized).

+  std::multimap<int, GURL> prerender_aliases_;
+  std::set<int> running_prerenders_;

[mmenke, 2012/09/12 16:31:45]

|running_prerenders_| doesn't seem to serve any purpose.  Also, if there's any
need to track running prerenders apart from prerender_aliases_, I'd suggest
combining them in a single map.

 };
 
 }  // namespace prerender
 
 #endif  // CHROME_RENDERER_PRERENDER_PRERENDER_DISPATCHER_H_