lib/action_mailer/base.rb in actionmailer-3.1.0.beta1 vs lib/action_mailer/base.rb in actionmailer-3.1.0.rc1

@@ -347,11 +347,10 @@
     include AbstractController::Layouts
     include AbstractController::Helpers
     include AbstractController::Translation
     include AbstractController::AssetPaths
 
-    cattr_reader :protected_instance_variables
-    @@protected_instance_variables = []
+    self.protected_instance_variables = %w(@_action_has_layout)
 
     helper  ActionMailer::MailHelper
     include ActionMailer::OldApi
 
     private_class_method :new #:nodoc: