[FIX] core: no traceback when closing socket.

Closes 5057

openerp/netsvc.py

@@ -57,6 +57,10 @@ def close_socket(sock):
     try:
         sock.shutdown(socket.SHUT_RDWR)
     except socket.error, e:
+        if e.errno == errno.EBADF:
+            # Werkzeug > 0.9.6 closes the socket itself (see commit
+            # https://github.com/mitsuhiko/werkzeug/commit/4d8ca089)
+            return
         # On OSX, socket shutdowns both sides if any side closes it
         # causing an error 57 'Socket is not connected' on shutdown
         # of the other side (or something), see