Don't separate node bindings into renderer and browser part.

Since we are going to use embeding thread to implement message
integration on all platforms, we do not need to separate renderer and
browser anymore.

common/node_bindings_mac.cc

@@ -45,13 +45,8 @@ void NodeBindingsMac::PollEvents() {
 }
 
 // static
-NodeBindings* NodeBindings::CreateInBrowser() {
-  return new NodeBindingsMac(true);
-}
-
-// static
-NodeBindings* NodeBindings::CreateInRenderer() {
-  return new NodeBindingsMac(false);
+NodeBindings* NodeBindings::Create(bool is_browser) {
+  return new NodeBindingsMac(is_browser);
 }
 
 }  // namespace atom