Add tests and Android patches for javadoc in java.text.*Format

The patches are needed due to new docs coming from OpenJDK 11.
1. The "rg" and "ca" locale extensions are not supported.
2. The "tz" extension will be supported but requires
  java.util.Calendar upgraded to OpenJDK 11
3. The "nu" extension has been supported.
4. Standalone month in SimpleDateFormat has been supported.

Bug: 205685050
Test: atest CtsLibcoreTestCases:libcore.java.text.NumberFormatTest
Test: atest CtsLibcoreTestCases:libcore.java.text.DateFormatTest
Change-Id: I02d9e18388b7837d1f2343a6df1cdfe5ae64a7f9
6 files changed