Fix FIXME: xstrdup should not be here

Hi,

This FIXME goes into my eyes, when I am about to modify something here,

  /* Name is allocated by name_of_child.  */
  /* FIXME: xstrdup should not be here.  */

This FIXME was introduced in the python pretty-pretter patches.

  Python pretty-printing [6/6]
  https://sourceware.org/ml/gdb-patches/2009-05/msg00467.html

create_child_with_value is called in two paths,

 1. varobj_list_children -> create_child -> create_child_with_value,
 2. install_dynamic_child -> install_dynamic_child -> varobj_add_child
    -> create_child_with_value

In path #1, 'name' is allocated by name_of_child, as the original
comment said, we don't have to duplicate NAME in
create_child_with_value.  In path #2, 'name' is got from
PyArg_ParseTuple, and we have to duplicate NAME.

This patch removes the call to xstrdup in create_child_with_value
and call xstrudp in update_dynamic_varobj_children (path #2).

gdb:

2013-10-04  Yao Qi  <yao@codesourcery.com>

	* varobj.c (create_child_with_value): Remove 'const' from the
	type of parameter 'name'.
	(varobj_add_child): Likewise.
	(install_dynamic_child): Remove 'const' from the type of
	parameter 'name'.
	(varobj_add_child): Likewise.
	(create_child_with_value): Likewise.  Update comments.  Don't
	duplicate 'name'.
	(update_dynamic_varobj_children): Duplicate 'name'
	and pass it to install_dynamic_child.
Move notif_queue and remote_async_get_pending_events_token to remote_state

This patch also removes notif_xfree, and don't pass it QUEUE_alloc, because
we don't have to free notif_client when the remote_notif_state is freed.

gdb:

2013-10-04  Yao Qi  <yao@codesourcery.com>

	* remote-notif.c (DECLARE_QUEUE_P): Remove.
	(notif_queue): Remove.
	(remote_notif_process): Add one parameter 'notif_queue'.
	Update comments.  Callers update.
	(remote_async_get_pending_events_token): Remove.
	(remote_notif_register_async_event_handler): Remove.
	(remote_notif_unregister_async_event_handler): Remove.
	(handle_notification): Add parameter 'notif_queue'.  Update
	comments.  Callers update.
	(notif_xfree): Remove.
	(remote_notif_state_allocate): New function.
	(remote_notif_state_xfree): New function.
	(_initialize_notif): Remove code to allocate queue.
	* remote-notif.h (DECLARE_QUEUE_P): Moved from remote-notif.c.
	(struct remote_notif_state): New.
	(handle_notification): Update declaration.
	(remote_notif_process): Likewise.
	(remote_notif_register_async_event_handler): Remove.
	(remote_notif_unregister_async_event_handler): Remove.
	(remote_notif_state_allocate): Declare.
	(remote_notif_state_xfree): Declare.
	* remote.c (struct remote_state) <notif_state>: New field.
	(remote_close): Don't call
	remote_notif_unregister_async_event_handler.  Call
	remote_notif_state_xfree.
	(remote_open_1): Don't call
	remote_notif_register_async_event_handler.  Call
	remote_notif_state_allocate.
Move pending_event to remote_notif_state.

This patch moves pending_event to remote_notif_state.  All pending
events are destroyed in remote_notif_state_xfree.  However,
discard_pending_stop_replies release pending event too, so the pending
event of stop notification is released twice, we need some refactor
here.  We add a new function discard_pending_stop_replies_in_queue
which only discard events in stop_reply_queue, and let
remote_notif_state_xfree release pending event for all notif_client.

After this change, discard_pending_stop_replies is only attached to
ifnerior_exit observer, so the INF can't be NULL any more.  The
NULL checking is removed too.

gdb:

2013-10-04  Yao Qi  <yao@codesourcery.com>

	* remote-notif.h (REMOTE_NOTIF_ID): New enum.
	(struct notif_client) <pending_event>: Moved
	to struct remote_notif_state.
	<id>: New field.
	(struct remote_notif_state) <pending_event>: New field.
	(notif_event_xfree): Declare.
	* remote-notif.c (handle_notification): Adjust.
	(notif_event_xfree): New function.
	(do_notif_event_xfree): Call notif_event_xfree.
	(remote_notif_state_xfree): Call notif_event_xfree to free
	each element in field pending_event.
	* remote.c (discard_pending_stop_replies): Remove declaration.
	(discard_pending_stop_replies_in_queue): Declare.
	(remote_close): Call discard_pending_stop_replies_in_queue
	instead of discard_pending_stop_replies.
	(remote_start_remote): Adjust.
	(stop_reply_xfree): Call notif_event_xfree.
	(notif_client_stop): Adjust initialization.
	(remote_notif_remove_all): Rename it to ...
	(remove_stop_reply_for_inferior): ... this.  Update comments.
	Don't check INF is NULL.
	(discard_pending_stop_replies): Return early if notif_state is
	NULL.  Adjust.  Don't check INF is NULL.
	(remote_notif_get_pending_events): Adjust.
 	(discard_pending_stop_replies_in_queue): New function.
	(remote_wait_ns): Likewise.