Editor: Fix Tag Overrun Behavior

[unit-tick]

Supplemental Fix to #118876. In that PR I was unable to set the overrun behaviour as recommended by @KoBeWi in this comment. This fix gets the overrun to behave properly by utilising the set_custom_minimum_size by plugging in the size it currently is, this is done when NOTIFICATION_READY is emitted.

[KoBeWi]

Why is this in NOTIFICATION_READY, not the constructor?

[unit-tick]

get_size does not return a value in the constructor.

[KoBeWi]

That's very hacky, but if it works... 🤔

[unit-tick]

Yeah, I spent the better part of a day trying to figure this out. At first I used get_minimum_size but the sizes it returned was all over the place. Using only x values, it returned 33px for the "Test" tag, which required 45px and 112 for "Development" which required 104px.

[StarryWorm]

Ideally, buttons would properly support the flag, but that would require changes out of scope for 4.7 (and yes, I will get it done for 4.8).
The solution you put forward is rather hacky, as KoBeWi pointed out, but it's contained to the editor tags, so I support it as a temporary solution. If it works, it works.

[unit-tick]

Yeah, I don't mind cleaning this up when buttons use internal labels as it'll no longer be a necessary bandaid.

[KoBeWi]

You could add a FIXME or HACK comment pointing at the better solution.

[Repiteo]

No need for a HACK and FIXME comment; just the one will suffice

[Repiteo]

Adjusted to fit our comment style guidelines:

Suggested change

	//HACK: can't be set in constructor because get_size() returns empty, will be made unnecessary when Button utilizes internal labels.
	if (p_what == NOTIFICATION_READY) {
	button->set_custom_minimum_size(get_size());
	button->set_text_overrun_behavior(TextServer::OverrunBehavior::OVERRUN_TRIM_ELLIPSIS); //FIXME: Move to constructor when Button utilizes internal labels.
	// HACK: Can't set overrun behavior in constructor because `get_size()` would return empty.
	// This logic should be migrated once `Button` utilizes internal labels.
	if (p_what == NOTIFICATION_READY) {
	button->set_custom_minimum_size(get_size());
	button->set_text_overrun_behavior(TextServer::OverrunBehavior::OVERRUN_TRIM_ELLIPSIS);