Ensure that StringIO is always available for the Schema dumper. [Marcel Molina Jr.]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4315 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

 *SVN*
 
+* Ensure that StringIO is always available for the Schema dumper. [Marcel Molina Jr.]
+
 * Allow AR::Base#to_xml to include methods too. Closes #4921. [johan@textdrive.com] 
 
 * Replace superfluous name_to_class_name variant with camelize. [Marcel Molina Jr.]

activerecord/lib/active_record/schema_dumper.rb

+require 'stringio'
+
 module ActiveRecord
   # This class is used to dump the database schema for some connection to some
   # output format (i.e., ActiveRecord::Schema).