Fix build breakage

Change-Id: Ia684fb55db301fdadaa3aae93f82b2cdcfc200af
diff --git a/services/tests/servicestests/src/com/android/server/NetworkStatsServiceTest.java b/services/tests/servicestests/src/com/android/server/NetworkStatsServiceTest.java
index 5fa046aa..a9909b2 100644
--- a/services/tests/servicestests/src/com/android/server/NetworkStatsServiceTest.java
+++ b/services/tests/servicestests/src/com/android/server/NetworkStatsServiceTest.java
@@ -63,6 +63,7 @@
 import android.net.NetworkStatsHistory;
 import android.net.NetworkTemplate;
 import android.os.INetworkManagementService;
+import android.os.WorkSource;
 import android.telephony.TelephonyManager;
 import android.test.AndroidTestCase;
 import android.test.suitebuilder.annotation.LargeTest;