Implement range-based for-statements.

	* cp-tree.def (RANGE_FOR_STMT): New.
	* cp-tree.h (RANGE_FOR_DECL, RANGE_FOR_EXPR, RANGE_FOR_BODY): New.
	(cp_convert_range_for): Declare.
	* pt.c (tsubst_expr): Add RANGE_FOR_STMT.
	(tsubst_copy_and_build): perform_koenig_lookup takes extra argument.
	* semantics.c (begin_range_for_stmt): New.
	(finish_range_for_decl): New.
	(finish_for_stmt): Accept also RANGE_FOR_STMT.
	(perform_koenig_lookup): Add extra argument include_std.
	* parser.c (cp_parser_c_for): New with code from
	cp_parser_iteration_statement().
	(cp_parser_range_for): New.
	(cp_convert_range_for): New.
	(cp_parser_iteration_statement): Add range-for support.
	(cp_parser_condition): Adjust comment.
	(cp_parser_postfix_expression): perform_koenig_lookup takes extra
	argument.
	* dump.c (cp_dump_tree): Add RANGE_FOR_STMT.
	* cxx-pretty-print.c: Likewise.
	* lex.c (cxx_init): Likewise.
	* name-lookup.c (lookup_function_nonclass): Add extra argument
	include_std.
	(lookup_arg_dependent): Likewise.
	* name-lookup.h: Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@164211 138bc75d-0d04-0410-961f-82ee72b054a4