[Remote suggestions] Add a remote suggestions flag to choose the source

components/ntp_snippets/features.h

 // Copyright 2016 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.
 
 #ifndef COMPONENTS_NTP_SNIPPETS_FEATURES_H_
 #define COMPONENTS_NTP_SNIPPETS_FEATURES_H_
 
 #include <memory>
 #include <string>
 
 #include "base/feature_list.h"
 #include "components/ntp_snippets/category_rankers/category_ranker.h"
 #include "components/prefs/pref_service.h"
 
 namespace base {
 class Clock;
 }
 
 namespace ntp_snippets {
 
 // Features to turn individual providers/categories on/off.
+// TODO(jkrcal): Rename to kRemoteSuggestionsFeature.
 extern const base::Feature kArticleSuggestionsFeature;
 extern const base::Feature kBookmarkSuggestionsFeature;
 extern const base::Feature kRecentOfflineTabSuggestionsFeature;
 extern const base::Feature kPhysicalWebPageSuggestionsFeature;
 extern const base::Feature kForeignSessionsSuggestionsFeature;;
 
 // Feature to allow the 'save to offline' option to appear in the snippets
 // context menu.
 extern const base::Feature kSaveToOfflineFeature;
 
 // Feature to allow offline badges to appear on snippets.
 extern const base::Feature kOfflineBadgeFeature;
 
-// Feature to allow specification of content suggestions source.
-// TODO(peconn): Figure out how to remove this, it is useful to specify the
-// source, but you shouldn't be able to disable it.
-extern const base::Feature kContentSuggestionsSource;
-
 // Feature to allow UI as specified here: https://crbug.com/660837.
 extern const base::Feature kIncreasedVisibility;
 
 // Feature to prefer AMP URLs over regular URLs when available.
 extern const base::Feature kPreferAmpUrlsFeature;
 
 // Feature to choose a category ranker.
 extern const base::Feature kCategoryRanker;
 
 // Parameter and its values for the kCategoryRanker feature flag.
@@ skipping 26 matching lines @@
   GENERAL,
   EMERGING_MARKETS_ORIENTED,
 };
 
 // Returns which category order to use according to kCategoryOrder feature.
 CategoryOrderChoice GetSelectedCategoryOrder();
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_FEATURES_H_