Follow API change.

Change-Id: I4652ebd2636f9de799d665a5939c3d376a418aaf
diff --git a/tests/src/com/android/contacts/widget/TestLoaderManager.java b/tests/src/com/android/contacts/widget/TestLoaderManager.java
index e964024..be9cb8c 100644
--- a/tests/src/com/android/contacts/widget/TestLoaderManager.java
+++ b/tests/src/com/android/contacts/widget/TestLoaderManager.java
@@ -30,7 +30,7 @@
  * A {@link LoaderManager} that performs synchronous loading on demand for unit
  * testing.
  */
-public class TestLoaderManager implements LoaderManager {
+public class TestLoaderManager extends LoaderManager {
 
     // Using a linked hash map to get all loading done in a predictable order.
     private LinkedHashMap<Integer, Loader<?>> mStartedLoaders = new LinkedHashMap<