Merge "Fix broken tests due to uninitialized roots." into nyc-dev

am: 621a71c342

* commit '621a71c342ab9c101b51a3b04db62792cfdbdcad':
  Fix broken tests due to uninitialized roots.

packages/DocumentsUI/tests/src/com/android/documentsui/ActivityTest.java

@@ -117,6 +117,8 @@ public abstract class ActivityTest<T extends Activity> extends ActivityInstrumen
         mClient = mResolver.acquireUnstableContentProviderClient(getTestingProviderAuthority());
         mDocsHelper = new DocumentsProviderHelper(getTestingProviderAuthority(), mClient);
 
+        setupTestingRoots();
+
         launchActivity();
         resetStorage();
     }