only ref non-default isolate loops

Author: Igor Zinkovsky

src/node_isolate.cc

@@ -269,6 +269,10 @@ Isolate::Isolate() {
     loop_ = uv_default_loop();
   } else {
     loop_ = uv_loop_new();
+    // Artificially ref the isolate loop so that the child
+    // isolate stays alive by default.  process.exit will
+    // unref the loop (see Isolate::Unref).
+    uv_ref(loop_);
   }
 
   debug_state = kNone;
@@ -280,11 +284,6 @@ Isolate::Isolate() {
   assert(v8_isolate_->GetData() == NULL);
   v8_isolate_->SetData(this);
 
-  // Artificially ref the isolate loop so that the child
-  // isolate stays alive by default.  process.exit will
-  // unref the loop (see Isolate::Unref).
-  uv_ref(loop_);
-
   globals_init_ = false;
 }