Address nit from aosp/1301317

Test: atest ConnectivityServiceTest#testVpnSetUnderlyingNetworks
Bug: 150570873
Change-Id: If5e5439b22f05e08a293fd83da4d54f6a4363ca5

tests/net/java/com/android/server/ConnectivityServiceTest.java

@@ -5493,6 +5493,8 @@ public class ConnectivityServiceTest {
         assertFalse(nc.hasTransport(TRANSPORT_WIFI));
         // For safety reasons a VPN without underlying networks is considered metered.
         assertFalse(nc.hasCapability(NET_CAPABILITY_NOT_METERED));
+        // A VPN without underlying networks is not suspended.
+        assertTrue(nc.hasCapability(NET_CAPABILITY_NOT_SUSPENDED));
 
         // Connect cell and use it as an underlying network.
         mCellNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_CELLULAR);