Use local defined constants for notification channels

ConnectivityService mainline module cannot call the members
inside SystemNotificationChannels.java. So use the local defined
constants instead.

Bug: 172040168
Test: atest FrameworksNetTests
Test: Manual test NO_INTERNET, SIGN_IN, PARTIAL_CONNECTIVITY,
      VPN_ALWAYS_ON notifications.
Change-Id: I223b207c4346e8239dee78e50dd2b0532a3e55b0
diff --git a/services/core/java/com/android/server/connectivity/NetworkNotificationManager.java b/services/core/java/com/android/server/connectivity/NetworkNotificationManager.java
index 3d22d6d..26eca19 100644
--- a/services/core/java/com/android/server/connectivity/NetworkNotificationManager.java
+++ b/services/core/java/com/android/server/connectivity/NetworkNotificationManager.java
@@ -41,7 +41,6 @@
 import com.android.internal.R;
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.messages.nano.SystemMessageProto.SystemMessage;
-import com.android.internal.notification.SystemNotificationChannels;
 
 public class NetworkNotificationManager {
 
@@ -72,7 +71,12 @@
 
     private static final String TAG = NetworkNotificationManager.class.getSimpleName();
     private static final boolean DBG = true;
-    private static final boolean VDBG = false;
+
+    // Notification channels used by ConnectivityService mainline module, it should be aligned with
+    // SystemNotificationChannels.
+    public static final String NOTIFICATION_NETWORK_STATUS = "NETWORK_STATUS";
+    public static final String NOTIFICATION_NETWORK_ALERTS = "NETWORK_ALERTS";
+    public static final String NOTIFICATION_VPN = "VPN";
 
     // The context is for the current user (system server)
     private final Context mContext;
@@ -255,8 +259,7 @@
         // the tag.
         final boolean hasPreviousNotification = previousNotifyType != null;
         final String channelId = (highPriority && !hasPreviousNotification)
-                ? SystemNotificationChannels.NETWORK_ALERTS
-                : SystemNotificationChannels.NETWORK_STATUS;
+                ? NOTIFICATION_NETWORK_ALERTS : NOTIFICATION_NETWORK_STATUS;
         Notification.Builder builder = new Notification.Builder(mContext, channelId)
                 .setWhen(System.currentTimeMillis())
                 .setShowWhen(notifyType == NotificationType.NETWORK_SWITCH)
diff --git a/services/core/java/com/android/server/connectivity/Vpn.java b/services/core/java/com/android/server/connectivity/Vpn.java
index 1a83272..dc4835a 100644
--- a/services/core/java/com/android/server/connectivity/Vpn.java
+++ b/services/core/java/com/android/server/connectivity/Vpn.java
@@ -26,6 +26,7 @@
 import static android.net.RouteInfo.RTN_UNREACHABLE;
 
 import static com.android.internal.util.Preconditions.checkNotNull;
+import static com.android.server.connectivity.NetworkNotificationManager.NOTIFICATION_VPN;
 
 import android.Manifest;
 import android.annotation.NonNull;
@@ -110,7 +111,6 @@
 import com.android.internal.net.VpnConfig;
 import com.android.internal.net.VpnInfo;
 import com.android.internal.net.VpnProfile;
-import com.android.internal.notification.SystemNotificationChannels;
 import com.android.internal.util.ArrayUtils;
 import com.android.server.ConnectivityService;
 import com.android.server.DeviceIdleInternal;
@@ -1942,7 +1942,7 @@
             final PendingIntent configIntent = mSystemServices.pendingIntentGetActivityAsUser(
                     intent, PendingIntent.FLAG_IMMUTABLE | PendingIntent.FLAG_UPDATE_CURRENT, user);
             final Notification.Builder builder =
-                    new Notification.Builder(mContext, SystemNotificationChannels.VPN)
+                    new Notification.Builder(mContext, NOTIFICATION_VPN)
                             .setSmallIcon(R.drawable.vpn_connected)
                             .setContentTitle(mContext.getString(R.string.vpn_lockdown_disconnected))
                             .setContentText(mContext.getString(R.string.vpn_lockdown_config))
diff --git a/services/core/java/com/android/server/net/LockdownVpnTracker.java b/services/core/java/com/android/server/net/LockdownVpnTracker.java
index 06cebac..661d38d 100644
--- a/services/core/java/com/android/server/net/LockdownVpnTracker.java
+++ b/services/core/java/com/android/server/net/LockdownVpnTracker.java
@@ -18,6 +18,8 @@
 
 import static android.provider.Settings.ACTION_VPN_SETTINGS;
 
+import static com.android.server.connectivity.NetworkNotificationManager.NOTIFICATION_VPN;
+
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.app.Notification;
@@ -42,7 +44,6 @@
 import com.android.internal.messages.nano.SystemMessageProto.SystemMessage;
 import com.android.internal.net.VpnConfig;
 import com.android.internal.net.VpnProfile;
-import com.android.internal.notification.SystemNotificationChannels;
 import com.android.server.ConnectivityService;
 import com.android.server.EventLogTags;
 import com.android.server.connectivity.Vpn;
@@ -256,7 +257,7 @@
 
     private void showNotification(int titleRes, int iconRes) {
         final Notification.Builder builder =
-                new Notification.Builder(mContext, SystemNotificationChannels.VPN)
+                new Notification.Builder(mContext, NOTIFICATION_VPN)
                         .setWhen(0)
                         .setSmallIcon(iconRes)
                         .setContentTitle(mContext.getString(titleRes))