Prerendering: Add MatchComplete PPLT

chrome/browser/prerender/prerender_manager.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_manager.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 59 matching lines @@
   "GET",
   "HEAD",
   "OPTIONS",
   "POST",
   "TRACE",
 };
 
 // Length of prerender history, for display in chrome://net-internals
 const int kHistoryLength = 100;
 
+// Indicates whether a Prerender has been cancelled such that we need
+// a dummy replacement for the purpose of recording the correct PPLT for
+// the Match Complete case.
+
+bool NeedMatchCompleteDummyForFinalStatus(FinalStatus final_status) {
+  return final_status != FINAL_STATUS_USED &&
+      final_status != FINAL_STATUS_TIMED_OUT &&
+      final_status != FINAL_STATUS_EVICTED &&
+      final_status != FINAL_STATUS_MANAGER_SHUTDOWN &&
+      final_status != FINAL_STATUS_WINDOW_OPENER &&
+      final_status != FINAL_STATUS_FRAGMENT_MISMATCH &&
+      final_status != FINAL_STATUS_CACHE_OR_HISTORY_CLEARED &&
+      final_status != FINAL_STATUS_CANCELLED &&
+      final_status != FINAL_STATUS_MATCH_COMPLETE_DUMMY;
+}
+
 }  // namespace
 
 class PrerenderManager::OnCloseTabContentsDeleter : public TabContentsDelegate {
  public:
   OnCloseTabContentsDeleter(PrerenderManager* manager,
                             TabContentsWrapper* tab)
       : manager_(manager),
         tab_(tab) {
     tab_->tab_contents()->set_delegate(this);
   }
@@ skipping 33 matching lines @@
 
 // static
 bool PrerenderManager::IsPrerenderingPossible() {
   return GetMode() == PRERENDER_MODE_ENABLED ||
          GetMode() == PRERENDER_MODE_EXPERIMENT_PRERENDER_GROUP ||
          GetMode() == PRERENDER_MODE_EXPERIMENT_CONTROL_GROUP ||
          GetMode() == PRERENDER_MODE_EXPERIMENT_NO_USE_GROUP;
 }
 
 // static
+bool PrerenderManager::ActuallyPrerendering() {
+  return IsPrerenderingPossible() && !IsControlGroup();
+}
+
+// static
 bool PrerenderManager::IsControlGroup() {
   return GetMode() == PRERENDER_MODE_EXPERIMENT_CONTROL_GROUP;
 }
 
 // static
 bool PrerenderManager::IsValidHttpMethod(const std::string& method) {
   // method has been canonicalized to upper case at this point so we can just
   // compare them.
   DCHECK_EQ(method, StringToUpperASCII(method));
   for (size_t i = 0; i < arraysize(kValidHttpMethods); ++i) {
@@ skipping 497 matching lines @@
     // No unload handler to run, so delete asap.
     ScheduleDeleteOldTabContents(old_tab_contents, NULL);
   }
 
   // TODO(cbentzel): Should prerender_contents move to the pending delete
   //                 list, instead of deleting directly here?
   AddToHistory(prerender_contents.get());
   return true;
 }
 
-void PrerenderManager::MoveEntryToPendingDelete(PrerenderContents* entry) {
+void PrerenderManager::MoveEntryToPendingDelete(PrerenderContents* entry,
+                                                FinalStatus final_status) {
   DCHECK(CalledOnValidThread());
+  DCHECK(entry);
   DCHECK(!IsPendingDelete(entry));
+
   for (std::list<PrerenderContentsData>::iterator it = prerender_list_.begin();
        it != prerender_list_.end();
        ++it) {
     if (it->contents_ == entry) {
-      prerender_list_.erase(it);
+      bool swapped_in_dummy_replacement = false;
+
+      // If this PrerenderContents is being deleted due to a cancellation,
+      // we need to create a dummy replacement for PPLT accounting purposes
+      // for the Match Complete group.
+      // This is the case if the cancellation is for any reason that would not
+      // occur in the control group case.
+      if (NeedMatchCompleteDummyForFinalStatus(final_status)) {
+        // TODO(tburkard): I'd like to DCHECK that we are actually prerendering.
+        // However, what if new conditions are added and
+        // NeedMatchCompleteDummyForFinalStatus, is not being updated.  Not sure
+        // what's the best thing to do here.  For now, I will just check whether
+        // we are actually prerendering.
+        if (ActuallyPrerendering()) {
+          PrerenderContents* dummy_replacement_prerender_contents =
+              CreatePrerenderContents(
+                  entry->prerender_url(),
+                  entry->referrer(),
+                  entry->origin(),
+                  entry->experiment_id());
+          if (dummy_replacement_prerender_contents &&
+              dummy_replacement_prerender_contents->Init()) {
+            it->contents_ = dummy_replacement_prerender_contents;
+            it->contents_->set_final_status(FINAL_STATUS_MATCH_COMPLETE_DUMMY);
+            swapped_in_dummy_replacement = true;
+          }
+        }
+      }
+      if (!swapped_in_dummy_replacement)
+        prerender_list_.erase(it);
       break;
     }
   }
   AddToHistory(entry);
   pending_delete_list_.push_back(entry);
 
   // Destroy the old TabContents relatively promptly to reduce resource usage,
   // and in the case of HTML5 media, reduce the change of playing any sound.
   PostCleanupTask();
 }
@@ skipping 51 matching lines @@
     const GURL& url) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   PrerenderManager* prerender_manager =
       PrerenderManagerFactory::GetForProfile(
           Profile::FromBrowserContext(tab_contents->browser_context()));
   if (!prerender_manager)
     return;
   if (!prerender_manager->is_enabled())
     return;
   bool was_prerender =
-      ((mode_ == PRERENDER_MODE_EXPERIMENT_CONTROL_GROUP &&
-        prerender_manager->WouldTabContentsBePrerendered(tab_contents)) ||
-       (mode_ == PRERENDER_MODE_EXPERIMENT_PRERENDER_GROUP &&
-        prerender_manager->IsTabContentsPrerendered(tab_contents)));
+      prerender_manager->IsTabContentsPrerendered(tab_contents);
+  bool was_complete_prerender = was_prerender ||
+      prerender_manager->WouldTabContentsBePrerendered(tab_contents);
   prerender_manager->histograms_->RecordPerceivedPageLoadTime(
-      perceived_page_load_time, was_prerender, url);
+      perceived_page_load_time, was_prerender, was_complete_prerender, url);
 }
 
 bool PrerenderManager::is_enabled() const {
   DCHECK(CalledOnValidThread());
   if (!enabled_)
     return false;
   for (std::list<const PrerenderCondition*>::const_iterator it =
            prerender_conditions_.begin();
        it != prerender_conditions_.end();
        ++it) {
@@ skipping 300 matching lines @@
   if (!render_process_host || !render_process_host->browser_context())
     return NULL;
   Profile* profile = Profile::FromBrowserContext(
       render_process_host->browser_context());
   if (!profile)
     return NULL;
   return PrerenderManagerFactory::GetInstance()->GetForProfile(profile);
 }
 
 }  // namespace prerender