overwrite_params no longer works with url_for

Overwrite_params is described here:
http://api.rubyonrails.org/classes/ActionController/Base.html

This functionality works in 2.3.5, and worked in 3.0 up to the following commit:

http://github.com/rails/rails/commit/226dfc2681c98deaf14e4ae82e973d...

An example of the breakage can be found at the bottom of the following page:

http://intertwingly.net/projects/AWDwR3/checkdepot/section-21.2.html

The same example under 2.3.5:

http://intertwingly.net/projects/AWDwR3/checkdepot-235/section-21.2...

Either this is an intentional change in behavior (and the rdocs need to be updated), or the function needs to be restored.