RFR: 8308644: [Linux] Simplify and fix small bugs on glass key related events

[Thiago Milczarek Sayao]

On Mon, 22 May 2023 00:19:45 GMT, Thiago Milczarek Sayao <tsayao at openjdk.org> wrote:

> While working on IME I noticed this code could be simplified, so I removed the `g_hash_table` usage for a simple struct ordered for binary search (I'm sure it's ordered because I did a simple app to generate it ordered).
> 
> This also fixes:
> 
> - UNKNOWN key codes being sent on KEY_PRESS;
> - Alt Gr is now working;
> - Replaced X calls with GDK calls for key locked check for as a small step towards supporting Wayland in the future
> - Added missing mappings (for F13 - F24 and dead keys) - Linux does not send dead keys as keypress but sends as key release, and they might be used on a robot test, so it's now covered.

@beldenfox AKA master of keys :)

Could you take a look?

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PR Comment: https://git.openjdk.org/jfx/pull/1143#issuecomment-1559127799