Don't do remove_possible_method when delegate is used. Two reasons: 1)...

Don't do remove_possible_method when delegate is used. Two reasons: 1) warnings should be shown, and fixed at the source and 2) the code is slow. Fixes #1937.

actionpack/lib/abstract_controller/layouts.rb

@@ -167,6 +167,7 @@ module Layouts
 
     included do
       class_attribute :_layout_conditions
+      remove_possible_method :_layout_conditions
       delegate :_layout_conditions, :to => :'self.class'
       self._layout_conditions = {}
       _write_layout_method

activesupport/lib/active_support/core_ext/module/delegation.rb

@@ -127,10 +127,6 @@ def delegate(*methods)
         end
 
       module_eval(<<-EOS, file, line - 5)
-        if instance_methods(false).map(&:to_s).include?("#{prefix}#{method}")
-          remove_possible_method("#{prefix}#{method}")
-        end
-
         def #{prefix}#{method}(*args, &block)               # def customer_name(*args, &block)
           #{to}.__send__(#{method.inspect}, *args, &block)  #   client.__send__(:name, *args, &block)
         rescue NoMethodError                                # rescue NoMethodError