Add ClearHistory() to ContentSuggestionsService and its providers

components/ntp_snippets/bookmarks/bookmark_suggestions_provider.cc

 // 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.
 
 #include "components/ntp_snippets/bookmarks/bookmark_suggestions_provider.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 166 matching lines @@
   MarkBookmarksDismissed(bookmark_model_, url);
 }
 
 void BookmarkSuggestionsProvider::FetchSuggestionImage(
     const std::string& suggestion_id,
     const ImageFetchedCallback& callback) {
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(callback, suggestion_id, gfx::Image()));
 }
 
+void BookmarkSuggestionsProvider::ClearHistory() {
+  // Not implemented.

[Marc Treib, 2016/08/29 09:43:11]

Add a TODO and reference the bug?

[vitaliii, 2016/08/29 10:37:25]

Done.

+}
+
 void BookmarkSuggestionsProvider::ClearCachedSuggestions(Category category) {
   DCHECK_EQ(category, provided_category_);
   // Ignored.
 }
 
 void BookmarkSuggestionsProvider::GetDismissedSuggestionsForDebugging(
     Category category,
     const DismissedSuggestionsCallback& callback) {
   DCHECK_EQ(category, provided_category_);
   std::vector<const BookmarkNode*> bookmarks =
@@ skipping 106 matching lines @@
 
 void BookmarkSuggestionsProvider::NotifyStatusChanged(
     CategoryStatus new_status) {
   if (category_status_ == new_status)
     return;
   category_status_ = new_status;
   observer()->OnCategoryStatusChanged(this, provided_category_, new_status);
 }
 
 }  // namespace ntp_snippets