Notify NetworkStatsService of roaming status changes.

When the roaming status of the cell network changes, it is handled as
follows:

-DcActiveState gets an event (either EVENT_DATA_CONNECTION_ROAM_ON or
 EVENT_DATA_CONNECTION_ROAM_OFF) and calls
 NetworkAgent#sendNetworkInfo with updated NetworkInfo.
-ConnectivityService then gets an EVENT_NETWORK_INFO_CHANGED and calls
 updateNetworkInfo with the new info.

With the previous code, the NetworkAgent's NetworkInfo object would be
updated internally, but because the state of the connection had not
changed from CONNECTED, the change would be considered a duplicate and
otherwise ignored.

With the new code, we call notifyIfacesChanged() when the state is the
same but the roaming status has changed. That should be all that is
necessary, as roaming is not exposed as a link property or network
capability today.

Bug: 26545456
Change-Id: I33d32d1fa84ce41dbe01542e5b498eda4b744b74

services/core/java/com/android/server/ConnectivityService.java

@@ -33,7 +33,6 @@ import static android.net.NetworkPolicyManager.RULE_REJECT_ALL;
 import static android.net.NetworkPolicyManager.RULE_REJECT_METERED;
 
 import android.annotation.Nullable;
-import android.app.AlarmManager;
 import android.app.BroadcastOptions;
 import android.app.Notification;
 import android.app.NotificationManager;
@@ -88,7 +87,6 @@ import android.os.PowerManager;
 import android.os.Process;
 import android.os.RemoteException;
 import android.os.ResultReceiver;
-import android.os.SystemClock;
 import android.os.SystemProperties;
 import android.os.UserHandle;
 import android.os.UserManager;
@@ -115,7 +113,6 @@ import com.android.internal.net.NetworkStatsFactory;
 import com.android.internal.net.VpnConfig;
 import com.android.internal.net.VpnInfo;
 import com.android.internal.net.VpnProfile;
-import com.android.internal.telephony.DctConstants;
 import com.android.internal.util.AsyncChannel;
 import com.android.internal.util.IndentingPrintWriter;
 import com.android.internal.util.XmlUtils;
@@ -155,11 +152,9 @@ import java.util.HashMap;
 import java.util.HashSet;
 import java.util.SortedSet;
 import java.util.TreeSet;
-import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.concurrent.atomic.AtomicInteger;
 
 /**
  * @hide
@@ -2186,7 +2181,7 @@ public class ConnectivityService extends IConnectivityManager.Stub
             if (wasDefault) {
                 mDefaultInetConditionPublished = 0;
             }
-            notifyIfacesChanged();
+            notifyIfacesChangedForNetworkStats();
             // TODO - we shouldn't send CALLBACK_LOST to requests that can be satisfied
             // by other networks that are already connected. Perhaps that can be done by
             // sending all CALLBACK_LOST messages (for requests, not listens) at the end
@@ -4095,7 +4090,7 @@ public class ConnectivityService extends IConnectivityManager.Stub
         }
         // TODO - move this check to cover the whole function
         if (!Objects.equals(newLp, oldLp)) {
-            notifyIfacesChanged();
+            notifyIfacesChangedForNetworkStats();
             notifyNetworkCallbacks(networkAgent, ConnectivityManager.CALLBACK_IP_CHANGED);
         }
 
@@ -4719,7 +4714,11 @@ public class ConnectivityService extends IConnectivityManager.Stub
         notifyLockdownVpn(networkAgent);
 
         if (oldInfo != null && oldInfo.getState() == state) {
-            if (VDBG) log("ignoring duplicate network state non-change");
+            if (oldInfo.isRoaming() != newInfo.isRoaming()) {
+                if (VDBG) log("roaming status changed, notifying NetworkStatsService");
+                notifyIfacesChangedForNetworkStats();
+            } else if (VDBG) log("ignoring duplicate network state non-change");
+            // In either case, no further work should be needed.
             return;
         }
         if (DBG) {
@@ -4749,7 +4748,7 @@ public class ConnectivityService extends IConnectivityManager.Stub
             }
             networkAgent.created = true;
             updateLinkProperties(networkAgent, null);
-            notifyIfacesChanged();
+            notifyIfacesChangedForNetworkStats();
 
             networkAgent.networkMonitor.sendMessage(NetworkMonitor.CMD_NETWORK_CONNECTED);
             scheduleUnvalidatedPrompt(networkAgent);
@@ -4913,9 +4912,10 @@ public class ConnectivityService extends IConnectivityManager.Stub
     }
 
     /**
-     * Notify other system services that set of active ifaces has changed.
+     * Notify NetworkStatsService that the set of active ifaces has changed, or that one of the
+     * properties tracked by NetworkStatsService on an active iface has changed.
      */
-    private void notifyIfacesChanged() {
+    private void notifyIfacesChangedForNetworkStats() {
         try {
             mStatsService.forceUpdateIfaces();
         } catch (Exception ignored) {
@@ -4949,7 +4949,7 @@ public class ConnectivityService extends IConnectivityManager.Stub
             success = mVpns.get(user).setUnderlyingNetworks(networks);
         }
         if (success) {
-            notifyIfacesChanged();
+            notifyIfacesChangedForNetworkStats();
         }
         return success;
     }