RFR: JDK-8294994: Update Jarsigner and Keytool i18n tests to validate i18n compliance

[Bill Huang]

On Mon, 10 Oct 2022 19:47:37 GMT, Naoto Sato <naoto at openjdk.org> wrote:

>> The jarsigner and keytool are localized into English, German, Japanese and Simplified Chinese. This task is to modify the existing i18n tests to validate i18n compliance in these tools. 
>> 
>> In addition, this task also contains changes for manual test enhancement and simplification which originated from [JDK-8292663](https://bugs.openjdk.org/browse/JDK-8292663.
>
> test/jdk/sun/security/tools/keytool/i18n.java line 250:
> 
>> 248:     private Thread currentThread = null;
>> 249: 
>> 250:     public static class DialogBuilder {
> 
> This seems to be a boilerplate for displaying the panel. Could this be separated from the test and converted into some library?

Sure, we can move this code to the library as there is no test code in it.

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PR: https://git.openjdk.org/jdk/pull/10635