hashtable_policy.h (_ReuseOrAllocNode): Use forward pattern.

2013-07-05  François Dumont  <fdumont@gcc.gnu.org>

	* include/bits/hashtable_policy.h (_ReuseOrAllocNode): Use forward
	pattern.
	(_MoveReuseOrAllocNode): Remove.
	(_Insert_base): Take a functor defining how the node is generated.
	* include/bits/hashtable.h: Adapt.
	(operator=(initializer_list<value_type>)): Reuse node if any.
	* testsuite/23_containers/unordered_set/instantiation_neg.cc:
	Adjust dg-error line number.
	* testsuite/23_containers/unordered_set/
	not_default_constructible_hash_neg.cc: Likewise.

From-SVN: r200724