Add ClearHistory() to ContentSuggestionsService and its providers

components/ntp_snippets/physical_web_pages/physical_web_page_suggestions_provider.cc

Index: components/ntp_snippets/physical_web_pages/physical_web_page_suggestions_provider.cc
diff --git a/components/ntp_snippets/physical_web_pages/physical_web_page_suggestions_provider.cc b/components/ntp_snippets/physical_web_pages/physical_web_page_suggestions_provider.cc
index 7f63e424338ef49aaabcbf1ead37dd7d57ef3d6e..f964417edb9a287140fb7556bd6ad51b78c0d65a 100644
--- a/components/ntp_snippets/physical_web_pages/physical_web_page_suggestions_provider.cc
+++ b/components/ntp_snippets/physical_web_pages/physical_web_page_suggestions_provider.cc
@@ -82,6 +82,10 @@ void PhysicalWebPageSuggestionsProvider::FetchSuggestionImage(
   // TODO(vitaliii): Implement.
 }
 
+void PhysicalWebPageSuggestionsProvider::ClearHistory() {
+  // Not implemented.

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

^^ :)

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

Acknowledged.

[Marc Treib, 2016/08/29 11:27:36]

Same here.

[vitaliii, 2016/08/29 16:46:42]

Done.

+}
+
 void PhysicalWebPageSuggestionsProvider::ClearCachedSuggestions(
     Category category) {
   // Ignored