* tracepoint.h (decode_agent_options): Add 'trace_string'

	* tracepoint.h (decode_agent_options): Add 'trace_string'
	argument.
	* tracepoint.c (decode_agent_options): Add 'trace_string'
	argument.
	(validate_actionline): Update.
	(collect_symbol): Add 'trace_string' argument.
	(struct add_local_symbols_data) <trace_string>: New field.
	(do_collect_symbol): Update.
	(add_local_symbols): Add 'trace_string' argument.
	(encode_actions_1): Update.
	(trace_dump_actions): Update.
	* dwarf2loc.c (access_memory): Update.
	* ax.h (struct agent_expr) <tracing, trace_string>: New fields.
	* ax-general.c (new_agent_expr): Update.
	* ax-gdb.h (gen_trace_for_expr, gen_trace_for_var)
	(gen_trace_for_return_address): Add argument.
	(trace_kludge, trace_string_kludge): Remove.
	* ax-gdb.c (trace_kludge, trace_string_kludge): Remove.
	(gen_traced_pop, gen_fetch, gen_bitfield_ref, gen_expr): Update.
	(gen_trace_for_var): Add 'trace_string' argument.
	(gen_trace_for_expr, gen_trace_for_return_address): Likewise.
	(gen_printf, agent_eval_command_one): Update.