Remove dead code

chrome/browser/history/top_sites_impl.cc

 // Copyright (c) 2013 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_impl.h"
 
 #include <algorithm>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 360 matching lines @@
   }
   ResetThreadSafeCache();
   NotifyTopSitesChanged();
 }
 
 void TopSitesImpl::Shutdown() {
   profile_ = NULL;
   // Cancel all requests so that the service doesn't callback to us after we've
   // invoked Shutdown (this could happen if we have a pending request and
   // Shutdown is invoked).
-  history_consumer_.CancelAllRequests();
+  cancelable_task_tracker_.TryCancelAll();

[blundell, 2014/07/22 15:19:57]

This is a behavioral change, as the two trackers have been merged into one. Do
you know that that's OK?

   backend_->Shutdown();
 }
 
 // static
 void TopSitesImpl::DiffMostVisited(const MostVisitedURLList& old_list,
                                    const MostVisitedURLList& new_list,
                                    TopSitesDelta* delta) {
 
   // Add all the old URLs for quick lookup. This maps URLs to the corresponding
   // index in the input.
@@ skipping 45 matching lines @@
 
   // Any member without the special marker in the all_old_urls list means that
   // there wasn't a "new" URL that mapped to it, so it was deleted.
   for (std::map<GURL, size_t>::const_iterator i = all_old_urls.begin();
        i != all_old_urls.end(); ++i) {
     if (i->second != kAlreadyFoundMarker)
       delta->deleted.push_back(old_list[i->second]);
   }
 }
 
-CancelableRequestProvider::Handle TopSitesImpl::StartQueryForMostVisited() {
+base::CancelableTaskTracker::TaskId TopSitesImpl::StartQueryForMostVisited() {
   DCHECK(loaded_);
   if (!profile_)
-    return 0;
+    return base::CancelableTaskTracker::kBadTaskId;
 
   HistoryService* hs = HistoryServiceFactory::GetForProfile(
       profile_, Profile::EXPLICIT_ACCESS);
   // |hs| may be null during unit tests.
   if (hs) {
     return hs->QueryMostVisitedURLs(
         num_results_to_request_from_history(),
         kDaysOfHistory,
         base::Bind(&TopSitesImpl::OnTopSitesAvailableFromHistory,
                    base::Unretained(this)),
         &cancelable_task_tracker_);
   }
-  return 0;
+  return base::CancelableTaskTracker::kBadTaskId;
 }
 
 bool TopSitesImpl::IsKnownURL(const GURL& url) {
   return loaded_ && cache_->IsKnownURL(url);
 }
 
 const std::string& TopSitesImpl::GetCanonicalURLString(const GURL& url) const {
   return cache_->GetCanonicalURL(url).spec();
 }
 
@@ skipping 455 matching lines @@
       base::TimeDelta::FromSeconds(kUpdateIntervalSecs));
 }
 
 void TopSitesImpl::OnTopSitesAvailableFromHistory(
     const MostVisitedURLList* pages) {
   DCHECK(pages);
   SetTopSites(*pages);
 }
 
 }  // namespace history