Fix test_send_object to avoid executing a callback after test destruction
Fix test_send_object to avoid executing a callback after test destruction

Fixes data race: http://pastebin.aldebaran.lan/view/9c8dd220
causing the segfault: http://pastebin.aldebaran.lan/view/eb1ec4aa

Change-Id: I71cae8643d402aee0858dd41ab24063740b4e114
Reviewed-on: http://gerrit.aldebaran.lan/76963
Reviewed-by: jlamotte <70353e7b0c7d18b7fc75605daf0ccba69fcd3222@aldebaran.com>
Reviewed-by: jmonnon <8898eaf233516e520f996a244ca8a12d20f948b1@aldebaran.com>
Tested-by: jlamotte <70353e7b0c7d18b7fc75605daf0ccba69fcd3222@aldebaran.com>

aldebaran/libqi,aldebaran/libqi,aldebaran/libqi