Create a new-installs-only uniformity trial.

chrome/browser/chrome_browser_main.cc

Index: chrome/browser/chrome_browser_main.cc
diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index 3f759042a41a8251de84d105f1f7c3a9d7ec239e..94be1c8dabe5dad4793e7ba7ab5fc7266b85a7d7 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -575,7 +575,11 @@ void ChromeBrowserMainParts::SetupMetricsAndFieldTrials() {
       browser_process_->variations_service();
   variations_service->CreateTrialsFromSeed(browser_process_->local_state());
 
-  browser_field_trials_.SetupFieldTrials();
+  int64 install_date = local_state_->GetInt64(

[Alexei Svitkine (slow), 2012/11/02 20:36:02]

nit: const

[SteveT, 2012/11/02 20:47:47]

Done.

+      prefs::kUninstallMetricsInstallDate);
+  // This must be called after the pref is initialized.
+  DCHECK(install_date);
+  browser_field_trials_.SetupFieldTrials(base::Time::FromTimeT(install_date));
 
   SetupPlatformFieldTrials();