net: add DNS certificate revocation experiment.

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 70e791fc7305e323fbf5d026da21c3bcc5f6e650..fdf68af7bfd10de75d7ae1f834af57e144b603ca 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -55,6 +55,7 @@
 #include "chrome/browser/metrics/tracking_synchronizer.h"
 #include "chrome/browser/nacl_host/nacl_process_host.h"
 #include "chrome/browser/net/chrome_net_log.h"
+#include "chrome/browser/net/chrome_network_delegate.h"
 #include "chrome/browser/net/predictor.h"
 #include "chrome/browser/notifications/desktop_notification_service.h"
 #include "chrome/browser/notifications/desktop_notification_service_factory.h"
@@ -1006,6 +1007,22 @@ void ChromeBrowserMainParts::AutoLaunchChromeFieldTrial() {
   }
 }
 
+void ChromeBrowserMainParts::ComodoDNSExperimentFieldTrial() {
+  // 100% probability of being in the experiment group until the timeout.
+  const base::FieldTrial::Probability kDivisor = 1;
+  const base::FieldTrial::Probability kProbability = 1;
+
+  // After April 15, 2012 builds, it will always be in default group.
+  scoped_refptr<base::FieldTrial> trial(
+      new base::FieldTrial("ComodoDNSExperiment", kDivisor,
+          "inactive", 2012, 4, 15));
+
+  const int active = trial->AppendGroup("active", kProbability);
+
+  if (trial->group() == active)
+    ChromeNetworkDelegate::EnableComodoDNSExperiment();
+}
+
 // ChromeBrowserMainParts: |SetupMetricsAndFieldTrials()| related --------------
 
 void ChromeBrowserMainParts::SetupFieldTrials(bool metrics_recording_enabled,
@@ -1026,6 +1043,7 @@ void ChromeBrowserMainParts::SetupFieldTrials(bool metrics_recording_enabled,
   PredictorFieldTrial();
   DefaultAppsFieldTrial();
   AutoLaunchChromeFieldTrial();
+  ComodoDNSExperimentFieldTrial();
   AutocompleteFieldTrial::Activate();
   NewTabUI::SetupFieldTrials();
 }