Specify the expected VPN network callbacks.

The test expects validated VPN network callbacks. However, an
unexpected Wi-Fi link bandwidth change during the test introduces
flakiness. To enhance test stability, specify the expected
callbacks to reduce flakiness.

Bug: 401489016
Test: atest CtsHostsideNetworkTests --iteration
Change-Id: I152ba5a4ff6c4a124db820f0eb58bb057e4dee5b
diff --git a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
index 3430196..a7938da 100755
--- a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
+++ b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
@@ -28,6 +28,7 @@
 import static android.net.ConnectivityManager.BLOCKED_REASON_NONE;
 import static android.net.ConnectivityManager.FIREWALL_CHAIN_BACKGROUND;
 import static android.net.ConnectivityManager.TYPE_VPN;
+import static android.net.NetworkCapabilities.NET_CAPABILITY_VALIDATED;
 import static android.net.NetworkCapabilities.TRANSPORT_TEST;
 import static android.net.NetworkCapabilities.TRANSPORT_VPN;
 import static android.os.Process.INVALID_UID;
@@ -1024,7 +1025,10 @@
         checkTrafficOnVpn();
 
         final Network vpnNetwork = mCM.getActiveNetwork();
-        myUidCallback.expectAvailableThenValidatedCallbacks(vpnNetwork, TIMEOUT_MS);
+        myUidCallback.eventuallyExpect(CallbackEntry.NETWORK_CAPS_UPDATED,
+                NETWORK_CALLBACK_TIMEOUT_MS,
+                entry -> entry.getNetwork().equals(vpnNetwork)
+                        && entry.getCaps().hasCapability(NET_CAPABILITY_VALIDATED));
         assertEquals(vpnNetwork, mCM.getActiveNetwork());
         assertNotEqual(defaultNetwork, vpnNetwork);
         maybeExpectVpnTransportInfo(vpnNetwork);