base: Change DCHECK_IS_ON to a macro DCHECK_IS_ON().

extensions/renderer/script_context_set.cc

Index: extensions/renderer/script_context_set.cc
diff --git a/extensions/renderer/script_context_set.cc b/extensions/renderer/script_context_set.cc
index 5ee9db4d2f1a0c69dfcb5c3c17416655facd2df5..5f7be6c156f84c6b031580b5ee4fcc486ae6171d 100644
--- a/extensions/renderer/script_context_set.cc
+++ b/extensions/renderer/script_context_set.cc
@@ -22,7 +22,7 @@ int ScriptContextSet::size() const {
 }
 
 void ScriptContextSet::Add(ScriptContext* context) {
-#if DCHECK_IS_ON
+#if DCHECK_IS_ON()
   // It's OK to insert the same context twice, but we should only ever have
   // one ScriptContext per v8::Context.
   for (ContextSet::iterator iter = contexts_.begin(); iter != contexts_.end();