PR c++/10603
	PR c++/12827
	* parser.c (cp_parser_error): Help c_parse_error print good
	messages if the next token is a keyword.
	(cp_parser_parameter_declaration_list): When resynchronizing after
	a bad parameter declaration, stop if a comma is found.
	(cp_parser_parameter_declaration): Avoid backtracking.

	PR c++/10603
	* g++.dg/parse/error6.C: New test.

	PR c++/12827
	* g++.dg/parse/error7.C: New test.

From-SVN: r74743