libcpp/

	* include/internal.h (_cpp_remaining_tokens_num_in_context): Take the
	context to act upon.
	* lex.c (_cpp_remaining_tokens_num_in_context): Likewise.  Update
	comment.
	(cpp_token_from_context_at): Likewise.
	(cpp_peek_token): Use the context to peek tokens from.

From-SVN: r180328