[Refional Preference] Fix test case fail

Test: make RunSettingsRoboTests -j128 ROBOTEST_FILTER=LocaleListEditorTest
Bug: 297304863
Change-Id: Ib59c033de3215c240b62a21885a6be4f813b292c
diff --git a/tests/robotests/src/com/android/settings/localepicker/LocaleListEditorTest.java b/tests/robotests/src/com/android/settings/localepicker/LocaleListEditorTest.java
index 5ff2baf..985f681 100644
--- a/tests/robotests/src/com/android/settings/localepicker/LocaleListEditorTest.java
+++ b/tests/robotests/src/com/android/settings/localepicker/LocaleListEditorTest.java
@@ -328,7 +328,6 @@
 
         mAdapter = spy(new LocaleDragAndDropAdapter(mLocaleListEditor, mLocaleList));
         ReflectionHelpers.setField(mAdapter, "mFeedItemList", mLocaleList);
-        ReflectionHelpers.setField(mAdapter, "mParent", mLocaleListEditor);
         ReflectionHelpers.setField(mAdapter, "mCacheItemList", new ArrayList<>(mLocaleList));
         ReflectionHelpers.setField(mAdapter, "mContext", mContext);
         ViewGroup view = new FrameLayout(mContext);