Fix AccountManagerServiceTest

The MockAccountAuthenticatorCache needs to implement the new method.

Bug: 6820670
Change-Id: I5d1cb3aecec63602ae4541cd01ae8e28c8328e5a

core/tests/coretests/src/android/accounts/AccountManagerServiceTest.java

@@ -216,6 +216,10 @@ public class AccountManagerServiceTest extends AndroidTestCase {
                 final RegisteredServicesCacheListener<AuthenticatorDescription> listener,
                 final Handler handler) {
         }
+
+        @Override
+        public void generateServicesMap() {
+        }
     }
 
     static public class MyMockContext extends MockContext {