Revert 244407 "InstantExtended: remove dead code related to the ..."

trunk/src/chrome/browser/search/instant_service.cc

Index: trunk/src/chrome/browser/search/instant_service.cc
===================================================================
--- trunk/src/chrome/browser/search/instant_service.cc	(revision 244428)
+++ trunk/src/chrome/browser/search/instant_service.cc	(working copy)
@@ -67,6 +67,8 @@
 
 InstantService::InstantService(Profile* profile)
     : profile_(profile),
+      ntp_prerenderer_(profile, this, profile->GetPrefs()),
+      browser_instant_controller_object_count_(0),
       weak_ptr_factory_(this) {
   // Stub for unit tests.
   if (!BrowserThread::CurrentlyOn(BrowserThread::UI))
@@ -122,6 +124,8 @@
 
   registrar_.Add(this, chrome::NOTIFICATION_GOOGLE_URL_UPDATED,
                  content::Source<Profile>(profile_->GetOriginalProfile()));
+  registrar_.Add(this, chrome::NOTIFICATION_PROFILE_DESTROYED,
+                 content::Source<Profile>(profile_));
 }
 
 InstantService::~InstantService() {
@@ -201,6 +205,37 @@
   instant_io_context_ = NULL;
 }
 
+scoped_ptr<content::WebContents> InstantService::ReleaseNTPContents() {
+  return ntp_prerenderer_.ReleaseNTPContents();
+}
+
+content::WebContents* InstantService::GetNTPContents() const {
+  return ntp_prerenderer_.GetNTPContents();
+}
+
+void InstantService::OnBrowserInstantControllerCreated() {
+  if (profile_->IsOffTheRecord())
+    return;
+
+  ++browser_instant_controller_object_count_;
+
+  if (browser_instant_controller_object_count_ == 1)
+    ntp_prerenderer_.ReloadInstantNTP();
+}
+
+void InstantService::OnBrowserInstantControllerDestroyed() {
+  if (profile_->IsOffTheRecord())
+    return;
+
+  DCHECK_GT(browser_instant_controller_object_count_, 0U);
+  --browser_instant_controller_object_count_;
+
+  // All browser windows have closed, so release the InstantNTP resources to
+  // work around http://crbug.com/180810.
+  if (browser_instant_controller_object_count_ == 0)
+    ntp_prerenderer_.DeleteNTPContents();
+}
+
 void InstantService::Observe(int type,
                              const content::NotificationSource& source,
                              const content::NotificationDetails& details) {
@@ -228,6 +263,16 @@
       break;
     }
 #endif  // defined(ENABLE_THEMES)
+    case chrome::NOTIFICATION_PROFILE_DESTROYED: {
+      // Last chance to delete InstantNTP contents. We generally delete
+      // preloaded InstantNTP when the last BrowserInstantController object is
+      // destroyed. When the browser shutdown happens without closing browsers,
+      // there is a race condition between BrowserInstantController destruction
+      // and Profile destruction.
+      if (GetNTPContents())
+        ntp_prerenderer_.DeleteNTPContents();
+      break;
+    }
     case chrome::NOTIFICATION_GOOGLE_URL_UPDATED: {
       OnGoogleURLUpdated(
           content::Source<Profile>(source).ptr(),
@@ -431,6 +476,10 @@
       InstantServiceObserver, observers_, DefaultSearchProviderChanged());
 }
 
+InstantNTPPrerenderer* InstantService::ntp_prerenderer() {
+  return &ntp_prerenderer_;
+}
+
 void InstantService::ResetInstantSearchPrerenderer() {
   if (!chrome::ShouldPrefetchSearchResults())
     return;