drawable_count was becoming negative. It tracks the number of
items in the worker->current_list ring. It was decremented correctly,
but incremented only in several cases. The cases it wasn't incremented
where:
 red_current_add_equal found an equivalent drawable
by moving the increment to where the item is added to current_list, in
__current_add_drawable, the accounting remains correct.

This has no affect other then correct accounting, as drawable_count isn't
used for anything.

While we are at it:  There is no reason for chardev
support to stay in the experimental area, so move it out.
qemu should not need the "spice-experimental.h" file.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit 7bbc2ba090788d844573e044041480ff6e3cba7b)

seamless stays in the experimental area.
comments updates too.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit 6acb817071daa13b8389bfce12cac6221997cebe)

Implement server-side support for switch-host client migration.  Client
side support is present already in the tree.

Setting the migration information is done using the existing
spice_server_migrate_info() function.  A new
spice_server_migrate_switch() function has been added which triggers
sending out the switch-host message.

Seamless migration functions are left there for now.
spice_server_migrate_start() has been chamnged to just fail
unconditionally though as seamless migration is broken anyway.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit 4b1ea4e102bb8a737487dab51dd0f3fc94352948)

We should pass up errors instead of aborting.  Do that at least
for bind() failures which actually happen in real live due to the
tcp port being busy.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit aafd8eea74acb23fc818b49824a74c4d885c3504)