RFR: 8342997: Remove use of System::getSecurityManager and SecurityManager [v5]

[Andy Goryachev]

On Wed, 13 Nov 2024 15:53:49 GMT, Kevin Rushforth <kcr at openjdk.org> wrote:

>> Ths PR removes all remaining calls to `System::getSecurityManager` and the `SecurityManager` class along with the `System.getGecurityManager() != null` code paths.
>> 
>> As part of doing this, the last uses of `PermissionHelper` and `FXPermissions` were eliminated, so I deleted those two classes. Since `PermissionHelper` was the last remaining use of `AccessControlException`, I am adding JDK-8342998 to this PR.
>> 
>> In a few places, I noted some "check permissions" methods that are now no-ops that might be candidates for further cleanup (not directly related, so not planned for jfx24).
>> 
>> Finally, I deleted several unused methods in `MethodUtil` and `ReflectUtil` (some of these were already removed in the corresponding JDK classes, and some of them were unused after the changes to remove the call to `getSecurityManager`).
>
> Kevin Rushforth has updated the pull request incrementally with one additional commit since the last revision:
> 
>   fix copy/paste error in comment

looks good

also checked for unused imports -
there are 540 unused import warnings, some in the generated code (can't be helped), some newly introduced by the junit5 conversion, and none in this PR.

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Marked as reviewed by angorya (Reviewer).

PR Review: https://git.openjdk.org/jfx/pull/1631#pullrequestreview-2433682201