Make it so disabled field trials are not reported as active.

base/metrics/field_trial.cc

Index: base/metrics/field_trial.cc
===================================================================
--- base/metrics/field_trial.cc	(revision 166931)
+++ base/metrics/field_trial.cc	(working copy)
@@ -145,7 +145,8 @@
 int FieldTrial::group() {
   FinalizeGroupChoice();
   if (!group_reported_) {
-    FieldTrialList::NotifyFieldTrialGroupSelection(name_, group_name_);
+    if (enable_field_trial_)

[Ilya Sherman, 2012/11/09 22:45:59]

optional nit: Maybe combine this with the if-stmt above?

[Alexei Svitkine (slow), 2012/11/09 23:42:39]

I thought of that, but then |group_reported_| wouldn't accurately track whether
group() was called externally (which wouldn't matter for the current use of that
variable, but may be useful to know in the future).

+      FieldTrialList::NotifyFieldTrialGroupSelection(name_, group_name_);
     group_reported_ = true;
   }
   return group_;
@@ -209,7 +210,7 @@
 }
 
 bool FieldTrial::GetActiveGroup(ActiveGroup* active_group) const {
-  if (!group_reported_)
+  if (!group_reported_ || !enable_field_trial_)
     return false;
   DCHECK_NE(group_, kNotFinalized);
   active_group->trial = name_;