fixing ungraceful daemon restart case where nw connect is not persisted

For graceful restart case it was done when the container was brought
down. But for ungraceful cases, the persistence is missing for nw
connect

Signed-off-by: Madhu Venugopal <madhu@docker.com>

daemon/container_unix.go

@@ -945,7 +945,13 @@ func (container *Container) ConnectToNetwork(idOrName string) error {
 	if !container.Running {
 		return derr.ErrorCodeNotRunning.WithArgs(container.ID)
 	}
-	return container.connectToNetwork(idOrName, true)
+	if err := container.connectToNetwork(idOrName, true); err != nil {
+		return err
+	}
+	if err := container.toDiskLocking(); err != nil {
+		return fmt.Errorf("Error saving container to disk: %v", err)
+	}
+	return nil
 }
 
 func (container *Container) connectToNetwork(idOrName string, updateSettings bool) error {
@@ -1177,7 +1183,14 @@ func (container *Container) DisconnectFromNetwork(n libnetwork.Network) error {
 		return derr.ErrorCodeNotRunning.WithArgs(container.ID)
 	}
 
-	return container.disconnectFromNetwork(n)
+	if err := container.disconnectFromNetwork(n); err != nil {
+		return err
+	}
+
+	if err := container.toDiskLocking(); err != nil {
+		return fmt.Errorf("Error saving container to disk: %v", err)
+	}
+	return nil
 }
 
 func (container *Container) disconnectFromNetwork(n libnetwork.Network) error {