* app.c (scrub_file): Remove.

	* app.c (scrub_file): Remove.
	(scrub_from_file, scrub_to_file): Remove.
	(scrub_string, scrub_last_string): Remove.
	(scrub_from_string, scrub_to_string): Remove.
	(saved_input, saved_input_len): New static variables.
	(struct app_saved): Remove scrub_string, scrub_last_string, and
	scrub_file fields.  Add saved_input and saved_input_len fields.
	(app_push): Adjust saved fields for changes in struct app_save.
	Initialize state and saved_input.
	(app_pop): Adjust saved fields for changes in struct app_save.
	(do_scrub_chars): Rename from do_scrub_next_char and rewrite to
	process a buffer at a time rather than a character at a time.
	(main, as_warn): Remove obsolete testing code.
	* as.h (do_scrub_next_char): Don't declare.
	(do_scrub_chars): Declare.
	(scrub_from_file, scrub_from_string): Don't declare.
	(scrub_to_file, scrub_to_string): Don't declare.
	* input-file.c (input_file_get): New static function.
	(input_file_give_next_buffer): Call do_scrub_chars rather than
	do_scrub_next_char.
	* read.c (scrub_string, scrub_string_end): New static variables.
	(scrub_from_string): New static function.
	(read_a_source_file): Call do_scrub_chars rather than
	do_scrub_next_char.
(and comment change in input-scrub.c)