Merge pull request #15741 from sgrif/sg-update-deprecation-message

Change the deprecation warning on `serialized_attributes`

activerecord/lib/active_record/attribute_methods/serialization.rb

@@ -50,14 +50,8 @@ def serialize(attr_name, class_name_or_coder = Object)
 
         def serialized_attributes
           ActiveSupport::Deprecation.warn(<<-WARNING.strip_heredoc)
-            `serialized_attributes` is deprecated, and will be removed in Rails 5.0.
-            If you need to access the serialization behavior, you can do:
-
-              #{self.class.name}.column_for_attribute('foo').type_cast_for_database(value)
-
-            or
-
-              #{self.class.name}.column_for_attribute('foo').type_cast_from_database(value)
+            `serialized_attributes` is deprecated without replacement, and will
+            be removed in Rails 5.0.
           WARNING
           @serialized_attributes ||= Hash[
             columns.select { |t| t.cast_type.is_a?(Type::Serialized) }.map { |c|