Minor cleanups to NetdCallbackReceiver.onEvent.

- Clean up identical error messages.
- Fix the array length check for InterfaceAddressChange.

Bug: 9180552
Change-Id: Id871f481445b530c3ad749725f1548df0e3a1228

services/tests/servicestests/src/com/android/server/NetworkManagementServiceTest.java

@@ -166,6 +166,9 @@ public class NetworkManagementServiceTest extends AndroidTestCase {
         sendMessage("614 Address removed 2001:db8::1/64 wlan0 1 0");
         expectSoon(observer).addressRemoved("2001:db8::1/64", "wlan0", 1, 0);
 
+        sendMessage("614 Address removed 2001:db8::1/64 wlan0 1");
+        // Not enough arguments.
+
         sendMessage("666 Address added 2001:db8::1/64 wlan0 1 0");
         // Invalid code.