Adding UMA metric to record the type of suggestion displayed on the NTP's Most Visited section.

chrome/browser/ui/webui/ntp/ntp_user_data_logger.h

Index: chrome/browser/ui/webui/ntp/ntp_user_data_logger.h
diff --git a/chrome/browser/ui/webui/ntp/ntp_user_data_logger.h b/chrome/browser/ui/webui/ntp/ntp_user_data_logger.h
index dc1df81ea28f2dd45a4f3b6f26d4e018fce78f3e..f4dc20378ddd39bd532de7e0431b7c0ab6fb4361 100644
--- a/chrome/browser/ui/webui/ntp/ntp_user_data_logger.h
+++ b/chrome/browser/ui/webui/ntp/ntp_user_data_logger.h
@@ -72,6 +72,10 @@ class NTPUserDataLogger
   // thumbnail image and that caused a fallback to the secondary thumbnail.
   size_t number_of_fallback_thumbnails_used_;
 
+  // True if at least one iframe came from a server-side suggestion. In
+  // practice, either all the iframes are server-side suggestions or none are.
+  bool server_side_suggestions_;
+
   // The URL of this New Tab Page - varies based on NTP version.
   GURL ntp_url_;