RefCounted types should not have public destructors, chrome/browser/ part 6

chrome/browser/metrics/field_trial_synchronizer.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/metrics/field_trial_synchronizer.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/threading/thread.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/metrics/experiments_helper.h"
 #include "chrome/common/render_messages.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_process_host.h"
 
 using content::BrowserThread;
 
+namespace {
+
+// This singleton instance should be constructed during the single threaded
+// portion of main(). It initializes globals to provide support for all future
+// calls. This object is created on the UI thread, and it is destroyed after
+// all the other threads have gone away.
+FieldTrialSynchronizer* g_field_trial_synchronizer = NULL;
+
+}  // namespace
+
 FieldTrialSynchronizer::FieldTrialSynchronizer() {
-  DCHECK(field_trial_synchronizer_ == NULL);
-  field_trial_synchronizer_ = this;
+  DCHECK(g_field_trial_synchronizer == NULL);
+  g_field_trial_synchronizer = this;
   base::FieldTrialList::AddObserver(this);
 
   experiments_helper::SetChildProcessLoggingExperimentList();
 }
 
-FieldTrialSynchronizer::~FieldTrialSynchronizer() {
-  base::FieldTrialList::RemoveObserver(this);
-  field_trial_synchronizer_ = NULL;
-}
-
 void FieldTrialSynchronizer::NotifyAllRenderers(
     const std::string& field_trial_name,
     const std::string& group_name) {
   // To iterate over RenderProcessHosts, or to send messages to the hosts, we
   // need to be on the UI thread.
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   for (content::RenderProcessHost::iterator it(
           content::RenderProcessHost::AllHostsIterator());
        !it.IsAtEnd(); it.Advance()) {
     it.GetCurrentValue()->Send(
         new ChromeViewMsg_SetFieldTrialGroup(field_trial_name, group_name));
   }
 }
 
 void FieldTrialSynchronizer::OnFieldTrialGroupFinalized(
     const std::string& field_trial_name,
     const std::string& group_name) {
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(&FieldTrialSynchronizer::NotifyAllRenderers,
                  this,
                  field_trial_name,
                  group_name));
   experiments_helper::SetChildProcessLoggingExperimentList();
 }
 
-// static
-FieldTrialSynchronizer*
-    FieldTrialSynchronizer::field_trial_synchronizer_ = NULL;
+FieldTrialSynchronizer::~FieldTrialSynchronizer() {
+  base::FieldTrialList::RemoveObserver(this);
+  g_field_trial_synchronizer = NULL;
+}