Fix permanently selected audio bus effects

[berrybus]

This allows the audio bus effects to be deselected if the focus changes to fix this bug. Here is a recording of the new behavior:

Screen.Recording.2023-12-06.at.11.28.41.PM.mov

This is my first PR, and I wasn't sure if this was the best way to do it. I'm open to any feedback. Thanks for taking a look!

Bugsquad edit:

• Fixes Unable to deselect Audio bus effects (including selecting nodes or files, switching tabs, etc.) #85478

[berrybus]

This works for some cases when focus is lost, but it's kind of annoying when your mouse is just hovering over another node like the scene editor. Is there a way to check "is left mouse button down" at this part? That way, it's clear that the user is intentionally clicking away.

[KoBeWi]

No. Other docks don't deselect on focus lost (e.g. file dock), rather they do it when you click away. Though then there is inspector, which doesn't allow deselecting properties 🤷‍♂️

You could use "empty_clicked" signal for deselecting. This means you'd need to click the empty space under effects, but they'd be deselectable in a predictable way at least. The empty space in bus layout (between buses) could be used too.

[berrybus]

Oh okay, the empty click event makes more sense. I'll try that, thanks! I couldn't find a generic one for "clicked somewhere else /outside/ of the current panel," so I guess that doesn't exist?

[KoBeWi]

Yep, clicking another control at most can steal focus.

[KoBeWi]

The solution could use some tweaks, as discussed in the comments, but it's already acceptable I think.

[akien-mga]

Is this equivalent to #42035?

[KoBeWi]

Yes, although the solution here is better.

[berrybus]

I was planning to use empty_clicked on the effects Tree and some "click empty space" method on the audio buses pane, but I could not find an easy way to check an "click empty space" event on the BoxContainer or ScrollContainer of the audio buses , so I've just gone ahead and renamed the focus_exited function.

And ah, yes it looks like someone else already made this change 3 years ago haha. I suppose y'all can decide which PR to merge!

EDIT: I did a force push to clean the commit log, hopefully that's okay

[KoBeWi]

I could not find an easy way to check an "click empty space" event on the BoxContainer or ScrollContainer of the audio buses

For stuff like generic containers you could use gui_input signal and check for mouse click, but it's not worth it.

[YuriSizov]

Thanks, and congrats on your first merged Godot contribution!

[YuriSizov]

Cherry-picked for 4.2.2.