Refactor render nothing/text => nil logic, and move to right place

Options :nothing and :text => nil should be handled by
ActionController::Rendering instead.

actionpack/lib/abstract_controller/rendering.rb

@@ -165,9 +165,6 @@ def _normalize_options(options)
         options[:prefixes] ||= _prefixes
       end
 
-      options[:text] = nil if options.delete(:nothing) == true
-      options[:text] = " " if options.key?(:text) && options[:text].nil?
-
       options[:template] ||= (options[:action] || action_name).to_s
       options
     end

actionpack/lib/action_controller/metal/rendering.rb

@@ -44,6 +44,10 @@ def _normalize_options(options) #:nodoc:
         options[:text] = options[:text].to_text
       end
 
+      if options.delete(:nothing) || (options.key?(:text) && options[:text].nil?)
+        options[:text] = " "
+      end
+
       if options[:status]
         options[:status] = Rack::Utils.status_code(options[:status])
       end