Clear browsing data from ContentSuggestionService only if exists.

chrome/browser/browsing_data/browsing_data_remover.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/browsing_data/browsing_data_remover.h"
 
 #include <map>
 #include <set>
 #include <string>
 
@@ skipping 504 matching lines @@
       waiting_for_clear_history_ = true;
       history_service->ExpireLocalAndRemoteHistoryBetween(
           WebHistoryServiceFactory::GetForProfile(profile_), std::set<GURL>(),
           delete_begin_, delete_end_,
           base::Bind(&BrowsingDataRemover::OnHistoryDeletionDone,
                      weak_ptr_factory_.GetWeakPtr()),
           &history_task_tracker_);
     }
 
     ntp_snippets::ContentSuggestionsService* content_suggestions_service =
-        ContentSuggestionsServiceFactory::GetForProfile(profile_);

[Marc Treib, 2016/09/15 12:45:09]

GetForProfile is called in one more place in this file, you should update that
too.

[jkrcal, 2016/09/15 12:53:17]

Oh, thanks for spotting that!

[Bernhard Bauer, 2016/09/15 13:44:46]

Should we add a DCHECK that the feature is enabled when constructing the service
so that we catch any regressions here?

+        ContentSuggestionsServiceFactory::GetForProfileIfExists(profile_);
     if (content_suggestions_service) {
       content_suggestions_service->ClearHistory(delete_begin_, delete_end_,
                                                 filter);
     }
 
 #if defined(ENABLE_EXTENSIONS)
     // The extension activity log contains details of which websites extensions
     // were active on. It therefore indirectly stores details of websites a
     // user has visited so best clean from here as well.
     // TODO(msramek): Support all backends with filter (crbug.com/589586).
@@ skipping 999 matching lines @@
   waiting_for_clear_offline_page_data_ = false;
   NotifyIfDone();
 }
 #endif
 
 void BrowsingDataRemover::OnClearedDomainReliabilityMonitor() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   waiting_for_clear_domain_reliability_monitor_ = false;
   NotifyIfDone();
 }