Revert accidental check-in. These changes are probably good, but premature at this point.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@174625 91177308-0d34-0410-b5e6-96231b3b80d8

include/functional

@@ -465,10 +465,6 @@ POLICY:  For non-variadic implementations, the number of arguments is limited
 #include <memory>
 #include <tuple>
 
-#if __OBJC__
-#  include <Foundation/NSObject.h>
-#endif
-
 #include <__functional_base>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
@@ -2024,26 +2020,6 @@ struct _LIBCPP_VISIBLE hash<long double>
     }
 };
 
-#if __OBJC__
-
-template <>
-struct _LIBCPP_VISIBLE hash<id>
-    : public unary_function<id, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(id __v) const _NOEXCEPT {return [__v hash];}
-};
-
-template <>
-struct _LIBCPP_VISIBLE equal_to<id>
-    : public binary_function<id, id, bool>
-{
-    _LIBCPP_INLINE_VISIBILITY bool operator()(id __x, id __y) const
-        {return __x == __y || [__x isEqual: __y];}
-};
-
-#endif  //  __OBJC__
-
 // struct hash<T*> in <memory>
 
 _LIBCPP_END_NAMESPACE_STD