Warnings in ActiveRecord

Hi,

I've made some fixes to remove warnings in AR, here they are
http://github.com/strzalek/rails/compare/rails:master...master

Could you look at them and push to rails master if you think they're
good? Any thoughts on this?

Thanks, Łukasz.

Forgot to mention - there is ticket about it in LH -
https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/5126-patch-warnings-about-shadowing-vars-in-ar#ticket-5126