2018-03-08  François Dumont  <fdumont@gcc.gnu.org>

	* python/libstdcxx/v6/printers.py (NodeIteratorPrinter): New.
	(StdListIteratorPrinter): Inherit from latter.
	(StdFwdListIteratorPrinter): New, inherit from latter.
	(StdDebugIteratorPrinter.to_string): Use non-debug iterator printer
	when iterator has no associated container.
	(build_libstdcxx_dictionary): Add __gnu_cxx::_Fwd_list_iterator and
	__gnu_cxx::_Fwd_list_const_iterator printers. Remove __norm namespace
	registrations.
	* testsuite/libstdc++-prettyprinters/debug.cc: Adapt.
	* testsuite/libstdc++-prettyprinters/debug_cxx11.cc: Adapt.

From-SVN: r258350