[opal-0.9] Fix dsl spec

Reason still requires investigration.

Author: zetachang

spec/react/dsl_spec.rb

@@ -82,8 +82,9 @@ def render
   end
 
   it "can add class names by the haml .class notation" do
-    stub_const 'Mod::Bar', Class.new(React::Component::Base)
+    stub_const 'Mod::Bar', Class.new
     Mod::Bar.class_eval do
+      include React::Component
       collect_other_params_as :attributes
       def render
         "a man walks into a bar".span(params.attributes)