Add time from navigation_start to NTP LogEvent

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 e723c697899f52c7a5f59538860594a2356e0539..55d8343a10a3f20afcb72a7e4c15918a02453248 100644
--- a/chrome/browser/ui/webui/ntp/ntp_user_data_logger.h
+++ b/chrome/browser/ui/webui/ntp/ntp_user_data_logger.h
@@ -41,9 +41,10 @@ class NTPUserDataLogger
   // the tab/shutting down Chrome), or when the user navigates to a URL.
   void EmitNtpStatistics();
 
-  // Called each time an event occurs on the NTP that requires a counter to be
-  // incremented.
-  void LogEvent(NTPLoggingEventType event);
+  // Called when an event occurs on the NTP that requires a counter to be
+  // incremented. The time parameters contains the time when this event occurred

[James Hawkins, 2015/03/19 19:59:59]

I don't understand what this parameter is supposed to be based on the comment. 
Is this a time delta?

[James Hawkins, 2015/03/19 19:59:59]

nit: s/parameters/parameter/

[James Hawkins, 2015/03/19 19:59:59]

Optional nit: You can just simply say "|time| contains the..."

[fserb, 2015/03/19 20:07:49]

Yes. Made it clearer.

[fserb, 2015/03/19 20:07:49]

Done.

[fserb, 2015/03/19 20:07:49]

Done.

+  // since navigation start.
+  void LogEvent(NTPLoggingEventType event, uint64 time);
 
   // Logs an impression on one of the Most Visited tiles by a given provider.
   void LogMostVisitedImpression(int position, const base::string16& provider);