JDK version:
jdk 11 build 12 failed
jdk 11 build 11 passed.

With default provider to run below test: "java Test2", Short week days, NaN value and timezone name are inconsistent between CLDR and Java in zh_CN, zh_TW locales.
For example, in CLDR, short week days in zh_CN is:<day type="sun">周日</day>, but Java output "星期日".

public class Test2 {

    public static void main(String[] args) throws Exception {
        DateFormatSymbols dfs;
        DateFormat df;
        DecimalFormat decimalf;
        DecimalFormatSymbols decimalfs;
        Locale zh_CN = Locale.forLanguageTag("zh-CN");
        Locale zh_TW = Locale.forLanguageTag("zh-TW");

        System.out.println("DateFormatSymbols.getShortWeekdays:");
        dfs = DateFormatSymbols.getInstance(zh_CN);
        String[] shortDays_zh_CN = dfs.getShortWeekdays();
        System.out.println("locale:zh_CN:" + shortDays_zh_CN[Calendar.SUNDAY]);

        dfs = DateFormatSymbols.getInstance(zh_TW);
        String[] shortDays_zh_TW = dfs.getShortWeekdays();
        System.out.println("locale:zh_TW:" + shortDays_zh_TW[Calendar.SUNDAY]);

        System.out.println("DateFormat.getTimeInstance.format:");
        TimeZone tz = TimeZone.getTimeZone("America/Los_Angeles");
        long l = 882869989318L;
        df = DateFormat.getTimeInstance(DateFormat.FULL, zh_CN);
        df.setTimeZone(tz);
        String fmt_zh_CN = df.format(new Date(l));
        System.out.println("locale:zh_CN:" + fmt_zh_CN);

        df = DateFormat.getTimeInstance(DateFormat.FULL, zh_TW);
        df.setTimeZone(tz);
        String fmt_zh_TW = df.format(new Date(l));
        System.out.println("locale:zh_TW:" + fmt_zh_TW);

        System.out.println("DecimalFormat.getNaN:");
        decimalf = (DecimalFormat) NumberFormat.getInstance(zh_CN);
        decimalfs = decimalf.getDecimalFormatSymbols();
        String nan_zh_CN = decimalfs.getNaN();
        System.out.println("locale:zh_CN:" + nan_zh_CN);

        decimalf = (DecimalFormat) NumberFormat.getInstance(zh_TW);
        decimalfs = decimalf.getDecimalFormatSymbols();
        String nan_zh_TW = decimalfs.getNaN();
        System.out.println("locale:zh_TW:" + nan_zh_TW);
    }
}
 
Except output:
DateFormatSymbols.getShortWeekdays:
locale:zh_CN:周日
locale:zh_TW:週日
DateFormat.getTimeInstance.format:
locale:zh_CN:北美太平洋标准时间 上午1:39:49
locale:zh_TW:上午1:39:49 [太平洋標準時間]
DecimalFormat.getNaN:
locale:zh_CN:NaN
locale:zh_TW:非數值

Actual output：
DateFormatSymbols.getShortWeekdays:
locale:zh_CN:星期日
locale:zh_TW:星期日
DateFormat.getTimeInstance.format:
locale:zh_CN:上午01时39分49秒 PST
locale:zh_TW:上午01時39分49秒 PST
DecimalFormat.getNaN:
locale:zh_CN:?
locale:zh_TW:?

Setting CLDR provider explicitly to run above test, "java -Djava.locale.providers=CLDR Test2", it can get expected output.