[NetworkPolicy]: Fixes the crash issues caused by null pointer.

When handleRegisterNetworkAgent in ConnectivityService,
the networkinfo of NetworkAgentInfo will be set to null.
So we need to handle the null pointer of state.networkInfo.

Change-Id: I2a278f1f1b2455057fd2ed323ff4df340c3cbca9
Signed-off-by: zhangshuxiao <zhangshuxiao@xiaomi.com>
1 file changed