Allow switch to anything from nullState

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

libcontainer/factory_linux.go

@@ -203,6 +203,9 @@ func (l *LinuxFactory) Load(id string) (Container, error) {
 		root:          containerRoot,
 	}
 	c.state = &nullState{c: c}
+	if err := c.refreshState(); err != nil {
+		return nil, err
+	}
 	return c, nil
 }
 

libcontainer/state_linux.go

@@ -214,12 +214,7 @@ func (n *nullState) status() Status {
 }
 
 func (n *nullState) transition(s containerState) error {
-	switch s.(type) {
-	case *restoredState:
-		n.c.state = s
-	default:
-		// do nothing for null states
-	}
+	n.c.state = s
 	return nil
 }