type_traits.h (_Bool): Removed this type.

	* bits/type_traits.h (_Bool): Removed this type.
	(__true_type, __false_type): Change to be plain structs.
	* src/string-inst.cc (__destroy_aux): Change third parm to be
	__false_type instead of _Bool<false>.
	* src/misc-inst.cc (__uninitialized_fill_n_aux,
	__uninitialized_copy_aux): Likewise.

From-SVN: r46383

libstdc++-v3/include/bits/type_traits.h

@@ -82,10 +82,8 @@ template <class _Tp> inline void copy(_Tp* __source,_Tp* __destination,int __n)
 }
 */
 
-
-template <bool _Truth> struct _Bool {};
-typedef _Bool<true>  __true_type;
-typedef _Bool<false> __false_type;
+struct __true_type {};
+struct __false_type {};
 
 template <class _Tp>
 struct __type_traits {