Remove @CorePlatformApi LocaleData usage in frameworks

They can be replaced by the public API provided by ICU4J instead.
No extra layer of caching equivalent to the LocaleData cache is
added because ICU4J has caches instances, e.g. DateFormatSymbols,
etc.

Bug: 160606356
Test: atest FrameworksCoreTests:android.text.format
Change-Id: I07048e0e1a4835d2744b7fce6a5ed79a112e456b