Support DISALLOW_CONFIG_LOCALE user restriction

Bug: 67586452
Test: make ROBOTEST_FILTER="(LocaleListEditorTest)" RunSettingsRoboTests\
&& make cts && cts-tradefed run cts-dev -m DevicePolicyManager \
-t com.android.cts.devicepolicy.UserRestrictionsTest

Change-Id: I2260b106a111078a62ae7628d6f60e976b70069c

src/com/android/settings/localepicker/LocaleDragAndDropAdapter.java

@@ -82,14 +82,13 @@ class LocaleDragAndDropAdapter
     }
 
     public LocaleDragAndDropAdapter(Context context, List<LocaleStore.LocaleInfo> feedItemList) {
-        this.mFeedItemList = feedItemList;
-
-        this.mContext = context;
+        mFeedItemList = feedItemList;
+        mContext = context;
 
         final float dragElevation = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,
                 context.getResources().getDisplayMetrics());
 
-        this.mItemTouchHelper = new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(
+        mItemTouchHelper = new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(
                 ItemTouchHelper.UP | ItemTouchHelper.DOWN, 0 /* no swipe */) {
 
             @Override
@@ -248,15 +247,6 @@ class LocaleDragAndDropAdapter
         return result;
     }
 
-    LocaleStore.LocaleInfo getFirstChecked() {
-        for (LocaleStore.LocaleInfo li : mFeedItemList) {
-            if (li.getChecked()) {
-                return li;
-            }
-        }
-        return null;
-    }
-
     void addLocale(LocaleStore.LocaleInfo li) {
         mFeedItemList.add(li);
         notifyItemInserted(mFeedItemList.size() - 1);