Handle case where user info might not be available.

The CursorLoader can return a null cursor if the query
failed for some reason.  This may happen in certain states
where the provider is not available.

Bug: 7133411
Change-Id: Id7b383bca45a61bc8726ba9f6115cbbc07e5d0b4

Author: Jeff Brown

packages/SystemUI/src/com/android/systemui/statusbar/phone/QuickSettings.java

@@ -404,7 +404,7 @@ private void queryForUserInformation() {
                     @Override
                     public void onLoadComplete(Loader<Cursor> loader,
                             Cursor cursor) {
-                        if (cursor.moveToFirst()) {
+                        if (cursor != null && cursor.moveToFirst()) {
                             String name = cursor.getString(0); // DISPLAY_NAME
                             mModel.setUserTileInfo(name);
                             /*