Prerendered pages are swapped in at browser::Navigate time.

chrome/browser/prerender/prerender_tab_helper.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/prerender/prerender_tab_helper.h"
 
 #include "base/metrics/histogram.h"
 #include "base/string_number_conversions.h"
 #include "base/time.h"
 #include "chrome/browser/prerender/prerender_manager.h"
@@ skipping 166 matching lines @@
 PrerenderTabHelper::~PrerenderTabHelper() {
 }
 
 void PrerenderTabHelper::ProvisionalChangeToMainFrameUrl(
     const GURL& url,
     const GURL& opener_url) {
   url_ = url;
   RecordPageviewEvent(PAGEVIEW_EVENT_NEW_URL);
   if (IsTopSite(url))
     RecordPageviewEvent(PAGEVIEW_EVENT_TOP_SITE_NEW_URL);
-  if (!tab_->core_tab_helper()->delegate())
-    return;  // PrerenderManager needs a delegate to handle the swap.
+  // TODO(cbentzel): Do we need to do the MarkWebContentsAsNotPrerendered()
+  // here? I assume it's for histograms.
   PrerenderManager* prerender_manager = MaybeGetPrerenderManager();
   if (!prerender_manager)
     return;
   if (prerender_manager->IsWebContentsPrerendering(web_contents()))
     return;
   prerender_manager->MarkWebContentsAsNotPrerendered(web_contents());
-  MaybeUsePrerenderedPage(url, opener_url);
 }
 
 void PrerenderTabHelper::UpdateTargetURL(int32 page_id, const GURL& url) {
   for (int i = 0; i < kNumHoverThresholds; i++)
     last_hovers_[i].RecordHover(url);
 
   if (url != current_hover_url_) {
     MaybeLogCurrentHover(false);
     current_hover_url_ = url;
     current_hover_time_ = base::TimeTicks::Now();
@@ skipping 34 matching lines @@
 
     MaybeLogCurrentHover(current_hover_url_ == validated_url);
   }
 }
 
 PrerenderManager* PrerenderTabHelper::MaybeGetPrerenderManager() const {
   return PrerenderManagerFactory::GetForProfile(
       Profile::FromBrowserContext(web_contents()->GetBrowserContext()));
 }
 
-bool PrerenderTabHelper::MaybeUsePrerenderedPage(const GURL& url,
-                                                 const GURL& opener_url) {
-  PrerenderManager* prerender_manager = MaybeGetPrerenderManager();
-  if (!prerender_manager)
-    return false;
-  DCHECK(!prerender_manager->IsWebContentsPrerendering(web_contents()));
-  return prerender_manager->MaybeUsePrerenderedPage(web_contents(),
-                                                    url,
-                                                    opener_url);
-}
-
 bool PrerenderTabHelper::IsPrerendering() {
   PrerenderManager* prerender_manager = MaybeGetPrerenderManager();
   if (!prerender_manager)
     return false;
   return prerender_manager->IsWebContentsPrerendering(web_contents());
 }
 
 void PrerenderTabHelper::PrerenderSwappedIn() {
   // Ensure we are not prerendering any more.
   DCHECK(!IsPrerendering());
@@ skipping 31 matching lines @@
 
   current_hover_url_ = GURL();
 }
 
 bool PrerenderTabHelper::IsTopSite(const GURL& url) {
   PrerenderManager* pm = MaybeGetPrerenderManager();
   return (pm && pm->IsTopSite(url));
 }
 
 }  // namespace prerender