removes Module#included_in_classes, which is no longer used

activesupport/lib/active_support/core_ext/module.rb

 require 'active_support/core_ext/module/aliasing'
 require 'active_support/core_ext/module/introspection'
 
-require 'active_support/core_ext/module/inclusion'
 require 'active_support/core_ext/module/attribute_accessors'
 require 'active_support/core_ext/module/attr_internal'
 require 'active_support/core_ext/module/attr_accessor_with_default'

activesupport/lib/active_support/core_ext/module/inclusion.rb

-class Module
-  # Returns the classes in the current ObjectSpace where this module has been
-  # mixed in according to Module#included_modules.
-  #
-  #   module M
-  #   end
-  #   
-  #   module N
-  #     include M
-  #   end
-  #   
-  #   class C
-  #     include M
-  #   end
-  #   
-  #   class D < C
-  #   end
-  #
-  #   p M.included_in_classes # => [C, D]
-  #
-  def included_in_classes
-    classes = []
-    ObjectSpace.each_object(Class) { |k| classes << k if k.included_modules.include?(self) }
-
-    classes.reverse.inject([]) do |unique_classes, klass| 
-      unique_classes << klass unless unique_classes.collect { |k| k.to_s }.include?(klass.to_s)
-      unique_classes
-    end
-  end
-end
\ No newline at end of file

activesupport/test/core_ext/module_test.rb

@@ -72,13 +72,6 @@ def setup
     @david = Someone.new("David", Somewhere.new("Paulina", "Chicago"))
   end
 
-  def test_included_in_classes
-    assert One.included_in_classes.include?(Ab)
-    assert One.included_in_classes.include?(Xy::Bc)
-    assert One.included_in_classes.include?(Yz::Zy::Cd)
-    assert !One.included_in_classes.include?(De)
-  end
-
   def test_delegation_to_methods
     assert_equal "Paulina", @david.street
     assert_equal "Chicago", @david.city