Currently, even when VPN Lockdown mode is enabled, incoming packets are not dropped if VPN is not connected. This commit fixed this issue. After this commit, If VPN Lockdown mode is enabled, incoming packets are dropped regardless of the VPN connectivity. Bug: 206482423 Test: atest TrafficControllerTest ConnectivityServiceTest PermissionMonitorTest Change-Id: If52ece613c8aac1073355e43b6fb9cb3fcc87d1d