[Panlingual] Improve performance of displaying app list in Settings.

- Use existed ApplicationInfo to get needed info.
 - Add unittest to AppLocaleUtil.java

Bug: b/238054165
Bug: b/231904717
Test: Maunal test passed
Test: atest passed
Change-Id: I23f354c366b45d4b684184b3366aeab913bcd3c8

src/com/android/settings/applications/appinfo/AppLocalePreferenceController.java

@@ -84,6 +84,6 @@ public class AppLocalePreferenceController extends AppInfoPreferenceControllerBa
     @VisibleForTesting
     boolean canDisplayLocaleUi() {
         return AppLocaleUtil
-                .canDisplayLocaleUi(mContext, mParent.getAppEntry().info.packageName, mListInfos);
+                .canDisplayLocaleUi(mContext, mParent.getAppEntry().info, mListInfos);
     }
 }