simplify tcpTx/RxPackets

On T+ this is mainline code, and the bpf program (netd.c)
does not support collecting tcp specific stats.

(note: this *is* a behaviour change, as it currently
just always returns 0, but UNSUPPORTED/-1 seems to make
more sense)

Test: TreeHugger
Bug: 294604315
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Ifda15e67d9167a2be98ab6f4e3817ff7c0bb3fea
diff --git a/framework-t/src/android/net/TrafficStats.java b/framework-t/src/android/net/TrafficStats.java
index dc4ac55..41cf63f 100644
--- a/framework-t/src/android/net/TrafficStats.java
+++ b/framework-t/src/android/net/TrafficStats.java
@@ -683,33 +683,13 @@
     /** {@hide} */
     @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
     public static long getMobileTcpRxPackets() {
-        long total = 0;
-        for (String iface : getMobileIfaces()) {
-            long stat = UNSUPPORTED;
-            try {
-                stat = getStatsService().getIfaceStats(iface, TYPE_TCP_RX_PACKETS);
-            } catch (RemoteException e) {
-                throw e.rethrowFromSystemServer();
-            }
-            total += addIfSupported(stat);
-        }
-        return total;
+        return UNSUPPORTED;
     }
 
     /** {@hide} */
     @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
     public static long getMobileTcpTxPackets() {
-        long total = 0;
-        for (String iface : getMobileIfaces()) {
-            long stat = UNSUPPORTED;
-            try {
-                stat = getStatsService().getIfaceStats(iface, TYPE_TCP_TX_PACKETS);
-            } catch (RemoteException e) {
-                throw e.rethrowFromSystemServer();
-            }
-            total += addIfSupported(stat);
-        }
-        return total;
+        return UNSUPPORTED;
     }
 
     /**