Improve performance of LocaleList with Resources

We allow each individual Resources object to select the best
Locale for the given APK. This allows one update to the configuration
instead of multiple updates, once the locale is chosen.

The Java locale is selected from the app context's locale.

Bug:28625993
Bug:27325465
Change-Id: I99e1e53f522e560f3b80bbd1e1c605f552dbdff0