Record first run startup metrics.

chrome/browser/chrome_browser_main.h

Index: chrome/browser/chrome_browser_main.h
diff --git a/chrome/browser/chrome_browser_main.h b/chrome/browser/chrome_browser_main.h
index bd8f03ef5af88e861b43aca81f3d6a1914e2e76a..4157654c25d9ef3568a69c4538b39e7423bef61d 100644
--- a/chrome/browser/chrome_browser_main.h
+++ b/chrome/browser/chrome_browser_main.h
@@ -215,8 +215,9 @@ void RecordBreakpadStatusUMA(MetricsService* metrics);
 void WarnAboutMinimumSystemRequirements();
 
 // Records the time from our process' startup to the present time in
-// the Startup.BrowserMessageLoopStartTime UMA histogram.
-void RecordBrowserStartupTime();
+// the Startup.BrowserMessageLoopStartTime UMA histogram (records
+// Startup.FirstRun.BrowserMessageLoopStartTime instead if |is_first_run|).

[jeremy, 2013/05/05 12:35:56]

2 histogram names seems confusing here, how about changing this comment to read:
Record time from process startup to present time in an UMA histogram.
|is_first_run| - is the current launch part of a first run.

[gab, 2013/05/06 16:19:54]

Done.

+void RecordBrowserStartupTime(bool is_first_run);
 
 // Records a time value to an UMA histogram in the context of the
 // PreReadExperiment field-trial. This also reports to the appropriate