Remove broken hack which has no effect.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4050 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

 *SVN*
 
+* Remove a hack intended to avoid unloading the same class twice, but which would not work anyways. [Nicholas Seckar]
+
 * Update Object.subclasses_of to locate nested classes. This affects Object.remove_subclasses_of in that nested classes will now be unloaded. [Nicholas Seckar]
 
 * Update Object.remove_subclasses_of to use Class.remove_class, reducing duplication. [Nicholas Seckar]

activesupport/lib/active_support/core_ext/object/extending.rb

@@ -9,7 +9,6 @@ def subclasses_of(*superclasses)
       next if # Exclude this class if
         (k.ancestors & superclasses).empty? || # It's not a subclass of our supers
         superclasses.include?(k) || # It *is* one of the supers
-        subclasses.include?(k) || # We already have it for some obscure reason
         eval("! defined?(::#{k})") || # It's not defined.
         eval("::#{k}").object_id != k.object_id
       subclasses << k