RFR: 8328402: Implement pausing functionality for the PassFailJFrame [v2]

[Phil Race]

On Wed, 20 Mar 2024 20:25:33 GMT, Alexander Zvegintsev <azvegint at openjdk.org> wrote:

>>> we need to add next to Pass/Fail a "Pause Timer" button, that
>> (a) stops the count down
>> (b) changes the Pause Timer to "Resume Timer"
>> ~~(c) disables Pass/Fail until the timer is resumed~~
>> the test will not have to pause or be aware - only the PassFailJFrame machinery.
>> ~~So the tester can do anything they want except exit the test in the paused mode.~~
>> 
>> This PR implements everything except the (c).
>> I see nothing wrong with completing the test from the paused state, and it does not add an extra click.  
>> 
>> 
>> Example screenshots:
>> 
>> ![image](https://github.com/openjdk/jdk/assets/77687766/65d34bf8-1e46-4e68-b39e-a77f257ec3c0)
>> ![image](https://github.com/openjdk/jdk/assets/77687766/3a43e059-2d48-46f3-9d1b-c2ab84fcce37)
>
> Alexander Zvegintsev has updated the pull request incrementally with two additional commits since the last revision:
> 
>  - TimeoutHandler -> TimeoutHandlerPanel
>  - review comments

Marked as reviewed by prr (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/18368#pullrequestreview-1950390181