Use NetdUtils instead of NetworkManagementService in Vpn

NetdUtils has the same method(e.g. setInterfaceUp) as
NetworkManagementService so using the one inside NetdUtils instead
and try to remove NetworkManagementService from Vpn in
the following commit.

Bug: 170598012
Test: atest FrameworksNetTests
Change-Id: I867556478fbc8c8ca8baa4e4c438a47b3beebe39
diff --git a/tests/net/java/com/android/server/connectivity/VpnTest.java b/tests/net/java/com/android/server/connectivity/VpnTest.java
index 32c6a75..9373da3 100644
--- a/tests/net/java/com/android/server/connectivity/VpnTest.java
+++ b/tests/net/java/com/android/server/connectivity/VpnTest.java
@@ -21,6 +21,8 @@
 import static android.content.pm.UserInfo.FLAG_PRIMARY;
 import static android.content.pm.UserInfo.FLAG_RESTRICTED;
 import static android.net.ConnectivityManager.NetworkCallback;
+import static android.net.INetd.IF_STATE_DOWN;
+import static android.net.INetd.IF_STATE_UP;
 
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
@@ -61,6 +63,7 @@
 import android.net.INetd;
 import android.net.Ikev2VpnProfile;
 import android.net.InetAddresses;
+import android.net.InterfaceConfigurationParcel;
 import android.net.IpPrefix;
 import android.net.IpSecManager;
 import android.net.IpSecTunnelInterfaceResponse;
@@ -870,17 +873,28 @@
                         eq(AppOpsManager.MODE_IGNORED));
     }
 
-    private NetworkCallback triggerOnAvailableAndGetCallback() {
+    private NetworkCallback triggerOnAvailableAndGetCallback() throws Exception {
         final ArgumentCaptor<NetworkCallback> networkCallbackCaptor =
                 ArgumentCaptor.forClass(NetworkCallback.class);
         verify(mConnectivityManager, timeout(TEST_TIMEOUT_MS))
                 .requestNetwork(any(), networkCallbackCaptor.capture());
 
+        // onAvailable() will trigger onDefaultNetworkChanged(), so NetdUtils#setInterfaceUp will be
+        // invoked. Set the return value of INetd#interfaceGetCfg to prevent NullPointerException.
+        final InterfaceConfigurationParcel config = new InterfaceConfigurationParcel();
+        config.flags = new String[] {IF_STATE_DOWN};
+        when(mNetd.interfaceGetCfg(anyString())).thenReturn(config);
         final NetworkCallback cb = networkCallbackCaptor.getValue();
         cb.onAvailable(TEST_NETWORK);
         return cb;
     }
 
+    private void verifyInterfaceSetCfgWithFlags(String flag) throws Exception {
+        // Add a timeout for waiting for interfaceSetCfg to be called.
+        verify(mNetd, timeout(TEST_TIMEOUT_MS)).interfaceSetCfg(argThat(
+                config -> Arrays.asList(config.flags).contains(flag)));
+    }
+
     @Test
     public void testStartPlatformVpnAuthenticationFailed() throws Exception {
         final ArgumentCaptor<IkeSessionCallback> captor =
@@ -892,6 +906,8 @@
         final Vpn vpn = startLegacyVpn(createVpn(primaryUser.id), (mVpnProfile));
         final NetworkCallback cb = triggerOnAvailableAndGetCallback();
 
+        verifyInterfaceSetCfgWithFlags(IF_STATE_UP);
+
         // Wait for createIkeSession() to be called before proceeding in order to ensure consistent
         // state
         verify(mIkev2SessionCreator, timeout(TEST_TIMEOUT_MS))
@@ -910,6 +926,8 @@
         final Vpn vpn = startLegacyVpn(createVpn(primaryUser.id), mVpnProfile);
         final NetworkCallback cb = triggerOnAvailableAndGetCallback();
 
+        verifyInterfaceSetCfgWithFlags(IF_STATE_UP);
+
         // Wait for createIkeSession() to be called before proceeding in order to ensure consistent
         // state
         verify(mConnectivityManager, timeout(TEST_TIMEOUT_MS)).unregisterNetworkCallback(eq(cb));