Make PrerenderHandle an observer of PrerenderContents.

chrome/browser/prerender/prerender_contents.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_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 61 matching lines @@
   };
 
   class Observer {
    public:
     // Signals that the prerender has started running.
     virtual void OnPrerenderStart(PrerenderContents* contents) = 0;
 
     // Signals that the prerender has stopped running.
     virtual void OnPrerenderStop(PrerenderContents* contents) = 0;
 
+    // Signals the discovery, through redirects, of a new alias for this
+    // prerender.
+    virtual void OnPrerenderAddAlias(PrerenderContents* contents,
+                                     const GURL& alias_url);
+
+    // Signals that this prerender has just become a MatchComplete replacement.
+    virtual void OnPrerenderCreatedMatchCompleteReplacement(
+        PrerenderContents* contents, PrerenderContents* replacement);
+
    protected:
     Observer();
     virtual ~Observer() = 0;
   };
 
   // A container for extra data on pending prerenders.
   struct PendingPrerenderInfo {
    public:
     PendingPrerenderInfo(
         base::WeakPtr<PrerenderHandle> weak_prerender_handle,
@@ skipping 30 matching lines @@
     MATCH_COMPLETE_REPLACEMENT,
     // A prerender that is a MatchComplete dummy, early in the process of being
     // created. This prerender should not fail. Record for MatchComplete, but
     // not Match.
     MATCH_COMPLETE_REPLACEMENT_PENDING,
   };
 
   virtual ~PrerenderContents();
 
   // All observers of a PrerenderContents are removed after the OnPrerenderStop
-  // event is sent, so there is no need for a RemoveObserver() method.
+  // event is sent, so there is no need to call RemoveObserver() in the normal
+  // use case.
   void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
 
   // For MatchComplete correctness, create a dummy replacement prerender
   // contents to stand in for this prerender contents that (which we are about
   // to destroy).
-  PrerenderContents* CreateMatchCompleteReplacement() const;
+  PrerenderContents* CreateMatchCompleteReplacement();
 
   bool Init();
 
   static Factory* CreateFactory();
 
   // Start rendering the contents in the prerendered state. If
   // |is_control_group| is true, this will go through some of the mechanics of
   // starting a prerender, without actually creating the RenderView.
   // |creator_child_id| is the id of the child process that caused the prerender
   // to be created, and is needed so that the prerendered URLs can be sent to it
@@ skipping 112 matching lines @@
   // This could happen with renderer-issued navigations, such as a
   // MouseEvent being dispatched by a link to a website installed as an app.
   bool IsCrossSiteNavigationPending() const;
 
   // Adds a pending prerender to the list. If |weak_prerender_handle| still
   // exists when this page is made visible, it will be launched.
   virtual void AddPendingPrerender(
       scoped_ptr<PendingPrerenderInfo> pending_prerender_info);
 
   // Reissues any pending prerender requests from the prerendered page.  Also
-  // clears the list of pending requests.
-  void StartPendingPrerenders();
+  // clears the list of pending requests. Sends notifications.
+  void PrepareForUse();
 
  protected:
   PrerenderContents(PrerenderManager* prerender_manager,
                     Profile* profile,
                     const GURL& url,
                     const content::Referrer& referrer,
                     Origin origin,
                     uint8 experiment_id);
 
   // These call out to methods on our Observers, using our observer_list_. Note
   // that NotifyPrerenderStop() also clears the observer list.
   void NotifyPrerenderStart();
   void NotifyPrerenderStop();
+  void NotifyPrerenderAddAlias(const GURL& alias_url);
+  void NotifyPrerenderCreatedMatchCompleteReplacement(
+      PrerenderContents* replacement);
 
   // Called whenever a RenderViewHost is created for prerendering.  Only called
   // once the RenderViewHost has a RenderView and RenderWidgetHostView.
   virtual void OnRenderViewHostCreated(
       content::RenderViewHost* new_render_view_host);
 
   content::NotificationRegistrar& notification_registrar() {
     return notification_registrar_;
   }
 
@@ skipping 115 matching lines @@
 
   // Caches pages to be added to the history.
   AddPageVector add_page_vector_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderContents);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_