Changes TopSites to access blacklist from prefs when necessary. I'm

chrome/browser/history/top_sites.cc

 // 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.
 
 #include "chrome/browser/history/top_sites.h"
 
 #include <algorithm>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 23 matching lines @@
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/web_contents.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 #include "grit/locale_settings.h"
 #include "grit/theme_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/image/image_util.h"
 
+using base::DictionaryValue;
 using content::BrowserThread;
 using content::NavigationController;
 
 namespace history {
 
 // How many top sites to store in the cache.
 static const size_t kTopSitesNumber = 20;
 
 // Max number of temporary images we'll cache. See comment above
 // temp_images_ for details.
@@ skipping 79 matching lines @@
 };
 
 }  // namespace
 
 TopSites::TopSites(Profile* profile)
     : backend_(NULL),
       cache_(new TopSitesCache()),
       thread_safe_cache_(new TopSitesCache()),
       profile_(profile),
       last_num_urls_changed_(0),
-      blacklist_(NULL),
       pinned_urls_(NULL),
       history_state_(HISTORY_LOADING),
       top_sites_state_(TOP_SITES_LOADING),
       loaded_(false) {
   if (!profile_)
     return;
 
   if (content::NotificationService::current()) {
     registrar_.Add(this, chrome::NOTIFICATION_HISTORY_URLS_DELETED,
                    content::Source<Profile>(profile_));
     // Listen for any nav commits. We'll ignore those not related to this
     // profile when we get the notification.
     registrar_.Add(this, content::NOTIFICATION_NAV_ENTRY_COMMITTED,
                    content::NotificationService::AllSources());
   }
 
   // We create update objects here to be sure that dictionaries are created
   // in the user preferences.
   DictionaryPrefUpdate(profile_->GetPrefs(),
-                       prefs::kNtpMostVisitedURLsBlacklist).Get();
-  DictionaryPrefUpdate(profile_->GetPrefs(),
                        prefs::kNtpMostVisitedPinnedURLs).Get();
 
   // Now the dictionaries are guaranteed to exist and we can cache pointers
   // to them.
-  blacklist_ =
-      profile_->GetPrefs()->GetDictionary(prefs::kNtpMostVisitedURLsBlacklist);
   pinned_urls_ =
       profile_->GetPrefs()->GetDictionary(prefs::kNtpMostVisitedPinnedURLs);
-  CHECK(blacklist_ != NULL);
-  CHECK(pinned_urls_ != NULL);
+  DCHECK(pinned_urls_ != NULL);
 }
 
 void TopSites::Init(const FilePath& db_name) {
   // Create the backend here, rather than in the constructor, so that
   // unit tests that do not need the backend can run without a problem.
   backend_ = new TopSitesBackend;
   backend_->Init(db_name);
   backend_->GetMostVisitedThumbnails(
       &top_sites_consumer_,
       base::Bind(&TopSites::OnGotMostVisitedThumbnails,
@@ skipping 193 matching lines @@
     // likely the user is first running Chrome. During this time we throttle
     // updating from history by 30 seconds. If the user creates a new tab page
     // during this window of time we force updating from history so that the new
     // tab page isn't so far out of date.
     timer_.Stop();
     StartQueryForMostVisited();
   }
 }
 
 bool TopSites::HasBlacklistedItems() const {
-  return !blacklist_->empty();
+  const DictionaryValue* blacklist =
+      profile_->GetPrefs()->GetDictionary(prefs::kNtpMostVisitedURLsBlacklist);
+  return blacklist && !blacklist->empty();
 }
 
 void TopSites::AddBlacklistedURL(const GURL& url) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   RemovePinnedURL(url);
   Value* dummy = Value::CreateNullValue();
   {
     DictionaryPrefUpdate update(profile_->GetPrefs(),
                                 prefs::kNtpMostVisitedURLsBlacklist);
@@ skipping 12 matching lines @@
                                 prefs::kNtpMostVisitedURLsBlacklist);
     DictionaryValue* blacklist = update.Get();
     blacklist->RemoveWithoutPathExpansion(GetURLHash(url), NULL);
   }
   ResetThreadSafeCache();
   NotifyTopSitesChanged();
 }
 
 bool TopSites::IsBlacklisted(const GURL& url) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  return blacklist_->HasKey(GetURLHash(url));
+  const DictionaryValue* blacklist =
+      profile_->GetPrefs()->GetDictionary(prefs::kNtpMostVisitedURLsBlacklist);
+  return blacklist && blacklist->HasKey(GetURLHash(url));
 }
 
 void TopSites::ClearBlacklistedURLs() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   {
     DictionaryPrefUpdate update(profile_->GetPrefs(),
                                 prefs::kNtpMostVisitedURLsBlacklist);
     DictionaryValue* blacklist = update.Get();
     blacklist->Clear();
   }
@@ skipping 480 matching lines @@
   NotifyTopSitesChanged();
 
   // Restart the timer that queries history for top sites. This is done to
   // ensure we stay in sync with history.
   RestartQueryForTopSitesTimer(GetUpdateDelay());
 }
 
 int TopSites::num_results_to_request_from_history() const {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  return kTopSitesNumber + blacklist_->size();
+  const DictionaryValue* blacklist =
+      profile_->GetPrefs()->GetDictionary(prefs::kNtpMostVisitedURLsBlacklist);
+  return kTopSitesNumber + (blacklist ? blacklist->size() : 0);
 }
 
 void TopSites::MoveStateToLoaded() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   MostVisitedURLList filtered_urls;
   PendingCallbackSet pending_callbacks;
   {
     base::AutoLock lock(lock_);
 
@@ skipping 104 matching lines @@
   SetTopSites(pages);
 
   // Used only in testing.
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_TOP_SITES_UPDATED,
       content::Source<TopSites>(this),
       content::Details<CancelableRequestProvider::Handle>(&handle));
 }
 
 }  // namespace history