Add ClearHistory() to ContentSuggestionsService and its providers

components/ntp_snippets/bookmarks/bookmark_suggestions_provider.cc

Index: components/ntp_snippets/bookmarks/bookmark_suggestions_provider.cc
diff --git a/components/ntp_snippets/bookmarks/bookmark_suggestions_provider.cc b/components/ntp_snippets/bookmarks/bookmark_suggestions_provider.cc
index 4e2cfdc6c85156ce455f4d6c78c29882e1af9592..cfd6932b5a0b12649b87f9f180ad8b8085b0ca2f 100644
--- a/components/ntp_snippets/bookmarks/bookmark_suggestions_provider.cc
+++ b/components/ntp_snippets/bookmarks/bookmark_suggestions_provider.cc
@@ -184,6 +184,13 @@ void BookmarkSuggestionsProvider::FetchSuggestionImage(
       FROM_HERE, base::Bind(callback, gfx::Image()));
 }
 
+void BookmarkSuggestionsProvider::ClearHistory(
+    base::Time begin,
+    base::Time end,
+    base::Callback<bool(const GURL& url)> filter) {
+  // TODO(vitaliii): Implement. See crbug.com/641321.
+}
+
 void BookmarkSuggestionsProvider::ClearCachedSuggestions(Category category) {
   DCHECK_EQ(category, provided_category_);
   // Ignored.