Supporting command line argument to force field trials

chrome/browser/net/http_pipelining_compatibility_client.cc

Index: chrome/browser/net/http_pipelining_compatibility_client.cc
diff --git a/chrome/browser/net/http_pipelining_compatibility_client.cc b/chrome/browser/net/http_pipelining_compatibility_client.cc
index 5366097c347119d874429e60c12cfa5bddf3327f..95d4d1a58077982549ad7bf1dc516d34fcea6164 100644
--- a/chrome/browser/net/http_pipelining_compatibility_client.cc
+++ b/chrome/browser/net/http_pipelining_compatibility_client.cc
@@ -307,8 +307,8 @@ void CollectPipeliningCapabilityStatsOnIOThread(
   }
   // After October 30, 2012 builds, it will always be in default group
   // (disable_network_stats).
-  trial = new base::FieldTrial(kTrialName, kDivisor,
-                               "disable_test", 2012, 10, 30);
+  trial = base::FieldTrial::CreateInstance(kTrialName, kDivisor, "disable_test",
+                                           2012, 10, 30);
 
   chrome::VersionInfo::Channel channel = chrome::VersionInfo::GetChannel();
   if (channel == chrome::VersionInfo::CHANNEL_CANARY) {