Merge 198707 "Record first run startup metrics."

chrome/common/startup_metric_utils.cc

Index: chrome/common/startup_metric_utils.cc
===================================================================
--- chrome/common/startup_metric_utils.cc	(revision 199532)
+++ chrome/common/startup_metric_utils.cc	(working copy)
@@ -65,7 +65,7 @@
   return *MainEntryPointTimeInternal();
 }
 
-void OnBrowserStartupComplete() {
+void OnBrowserStartupComplete(bool is_first_run) {
   // Bail if uptime < 7 minutes, to filter out cases where Chrome may have been
   // autostarted and the machine is under io pressure.
   const int64 kSevenMinutesInMilliseconds =
@@ -85,9 +85,15 @@
   //   cases where Chrome is auto-started and IO is heavily loaded.
   base::TimeDelta startup_time_from_main_entry =
       base::Time::Now() - MainEntryStartTime();
-  UMA_HISTOGRAM_LONG_TIMES(
-      "Startup.BrowserMessageLoopStartTimeFromMainEntry",
-      startup_time_from_main_entry);
+  if (is_first_run) {
+    UMA_HISTOGRAM_LONG_TIMES(
+        "Startup.BrowserMessageLoopStartTimeFromMainEntry.FirstRun",
+        startup_time_from_main_entry);
+  } else {
+    UMA_HISTOGRAM_LONG_TIMES(
+        "Startup.BrowserMessageLoopStartTimeFromMainEntry",
+        startup_time_from_main_entry);
+  }
 
   // Create another histogram that records the exact number for use by
   // performance tests.