ecore_con: send server_upgrade event *after* clearing pending saves

ecore_con: send server_upgrade event *after* clearing pending saves

Summary:
The _ecore_con_post_event_server_upgrade() call adds an event to free
the server_upgrade object, svr, via  _ecore_con_server_free(svr) so we
should assume srv is freed after it returns.  Thus, perform the
pending_slice processing prior to calling it.  Otherwise it triggers an
illegal access (USE_AFTER_FREE) error in Coverity.

@fix CID1373485

Reviewers: barbieri

Reviewed By: barbieri

Subscribers: cedric, jpeg

Differential Revision: https://phab.enlightenment.org/D4785

Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>