Ui::scroll_to_me cannot be called for two separate ScrollArea during the same frame

[abey79]

Ui::scroll_to_me appears to use a single, global state to store the scroll target (FrameState::scroll_target). This means that it's not possible to change the scroll position of two separate scroll areas during the same frame. This is a problem e.g. for rerun-io/rerun#5232, where two scroll area should scroll to focused item at the same time.

[emilk]

Having two calls to scroll_to_me in two separate ScrollArea:s should already work

[abey79]

The situation was way more complicated than that and a couple of bugs were eventually found:

• Fix two ScrollArea bugs: leaking scroll target and broken animation to target offset #4174