include ActionView::Rendering in the minimal controller

without this module, the content type is not set correctly

actionpack/lib/action_controller/metal.rb

@@ -177,7 +177,7 @@ def content_type=(type)
     end
 
     def content_type
-      request.content_type
+      response.content_type
     end
 
     def location

actionpack/test/controller/new_base/render_html_test.rb

@@ -4,6 +4,7 @@ module RenderHtml
   class MinimalController < ActionController::Metal
     include AbstractController::Rendering
     include ActionController::Rendering
+    include ActionView::Rendering
 
     def index
       render html: "Hello World!"