8039969: Old Korean Calendar conflicts with Host Locale
8049835: [ar/HOST adapter] Hijri calendar era is used but date number follows gregorian
8054010: [HOST provider, not gregory] Return NULL when calling Calendar.getDisplayNames for Calendar.ERA
8054482: [HOST provider] only return standalone-style month display name
8055258: [HOST provider] Short era display name is not returned
Reviewed-by: okutsu
3f8548453c