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..0886eb90bd113ba48290b298a7b96db37b33a83b 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 +82,11 @@ void PhysicalWebPageSuggestionsProvider::FetchSuggestionImage(
   // TODO(vitaliii): Implement.
 }
 
+void PhysicalWebPageSuggestionsProvider::ClearHistory(base::Time begin,
+                                                      base::Time end) {
+  // TODO(vitaliii): Implement.

[Marc Treib, 2016/08/30 09:50:18]

Bug?

[vitaliii, 2016/08/30 11:04:22]

Done.

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