favor DCHECK_CURRENTLY_ON for better logs in chrome/browser/media_galleries , metrics and nacl_host

chrome/browser/metrics/field_trial_synchronizer.cc

Index: chrome/browser/metrics/field_trial_synchronizer.cc
diff --git a/chrome/browser/metrics/field_trial_synchronizer.cc b/chrome/browser/metrics/field_trial_synchronizer.cc
index cc9775a1ba2b83475269f28d968fc112de3b575d..43f53ad9c206174d9a955e8d07082f657db55a63 100644
--- a/chrome/browser/metrics/field_trial_synchronizer.cc
+++ b/chrome/browser/metrics/field_trial_synchronizer.cc
@@ -38,7 +38,7 @@ void FieldTrialSynchronizer::NotifyAllRenderers(
     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));
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
   for (content::RenderProcessHost::iterator it(
           content::RenderProcessHost::AllHostsIterator());