Make PrerenderHandle an observer of PrerenderContents.

chrome/browser/prerender/prerender_manager.h

Index: chrome/browser/prerender/prerender_manager.h
diff --git a/chrome/browser/prerender/prerender_manager.h b/chrome/browser/prerender/prerender_manager.h
index 806717015efb6188c06f4e7977f4f62c7918cb31..f4e4f0f475f95c799ba6764247154ba68ee4f3a6 100644
--- a/chrome/browser/prerender/prerender_manager.h
+++ b/chrome/browser/prerender/prerender_manager.h
@@ -267,10 +267,6 @@ class PrerenderManager : public base::SupportsWeakPtr<PrerenderManager>,
    public:
     struct OrderByExpiryTime;
 
-    // Constructor for a pending prerender, which will get its contents later.
-    explicit PrerenderData(PrerenderManager* manager);
-
-    // Constructor for an active prerender.
     PrerenderData(PrerenderManager* manager,
                   PrerenderContents* contents,
                   base::TimeTicks expiry_time);
@@ -282,18 +278,18 @@ class PrerenderManager : public base::SupportsWeakPtr<PrerenderManager>,
     void MakeIntoMatchCompleteReplacement();
 
     // A new PrerenderHandle has been created for this PrerenderData.
-    void OnNewHandle();
+    void OnNewHandle(PrerenderHandle* prerender_handle);

[mmenke, 2012/12/06 22:22:15]

I think "OnHandleCreated" seems to fit in a bit more with common Chrome naming
conventions, and the others as well.

[gavinp, 2012/12/10 17:55:10]

Done.

 
     // The launcher associated with a handle is navigating away from the context
     // that launched this prerender. If the prerender is active, it may stay
     // alive briefly though, in case we we going through a redirect chain that
     // will eventually land at it.
-    void OnNavigateAwayByHandle();
+    void OnNavigateAwayByHandle(PrerenderHandle* prerender_handle);
 
     // The launcher associated with a handle has taken explicit action to cancel
     // this prerender. We may well destroy the prerender in this case if no
     // other handles continue to track it.
-    void OnCancelByHandle();
+    void OnCancelByHandle(PrerenderHandle* prerender_handle);

[mmenke, 2012/12/06 22:22:15]

I'd suggest OnHandleNavigatedAway and OnHandleCanceled, but I don't feel as
strongly about it as "OnHandleCreated".  The old names are perhaps a bit more
accurate, but I prefer the parallel names.

If you prefer to keep your names, suggest changing them to past tense.

[gavinp, 2012/12/10 17:55:10]

Done. Good work using the American spelling of "Canceled."

[mmenke, 2012/12/11 19:53:45]

Thanks.  It's one of the few cases where I hate the American spelling.

[gavinp, 2012/12/13 13:38:03]

Wait: the American spelling is "Canceled." Would you like these methods renamed
to use the Canadian spelling of "Cancelled" ?

 
     PrerenderContents* contents() { return contents_.get(); }
 
@@ -334,11 +330,6 @@ class PrerenderManager : public base::SupportsWeakPtr<PrerenderManager>,
       ScopedVector<PrerenderContents::PendingPrerenderInfo>* pending_prerenders,
       content::SessionStorageNamespace* session_storage_namespace);
 
-  // Called by a PrerenderData to self-destroy, but only when the PrerenderData
-  // is pending (as in not yet active). Should not be called except for
-  // objects known to be in |pending_prerender_list_|.
-  void DestroyPendingPrerenderData(PrerenderData* pending_prerender_data);
-
   // Called by a PrerenderData to signal that the launcher has navigated away
   // from the context that launched the prerender. A user may have clicked
   // a link in a page containing a <link rel=prerender> element, or the user
@@ -518,9 +509,6 @@ class PrerenderManager : public base::SupportsWeakPtr<PrerenderManager>,
   // All running prerenders. Sorted by expiry time, in ascending order.
   ScopedVector<PrerenderData> active_prerenders_;
 
-  // All pending prerenders.
-  ScopedVector<PrerenderData> pending_prerenders_;
-
   // Prerenders awaiting deletion.
   ScopedVector<PrerenderData> to_delete_prerenders_;