[3.x] Bind TabContainer::get_tab_idx_at_point() to ClassDB

[nobuyukinyuu]

(Note: this is the 3.x-ready branch for #52050.)

As it currently stands, there's no reliable way from the GDScript to determine which tab the mouse is over, which is pretty important for being able to generate a relevant tooltip. This binds the already-used internal method to determine this to ClassDB.

[YeldhamDev]

This should be pushed towards the master branch, documented, and also binding the Tabs version.

[nobuyukinyuu]

Tabs already contains the tab_hover signal which performs this function, and the implementation between the controls is different. I assume documentation PRs go on the godot-docs repo but it likely won't be accepted for a feature that doesn't exist (yet). Luckily, the use case is pretty straightforward.

[YeldhamDev]

Tabs already contains the tab_hover signal which performs this function

Then it would be better to implement tab_hover in TabContainer if possible, so their interfaces remain similar.

I assume documentation PRs go on the godot-docs repo

I meant the internal XML docs. Run --doctool with the compiled binary to create an entry.

The point about the master branch still stands.

[nobuyukinyuu]

There is an open proposal regarding the differences in implementation here. Changing the general implementation between the controls is outside of the scope of this PR. I'm only submitting it because I need the feature. (I'll submit a separate PR which can merge with master shortly!)

[nobuyukinyuu]

Repo updated with changes to XML, commits squashed and description updated to point to the version that can be merged with master.

[groud]

Thanks!