As I look into re-implementing the ability to choose combo colour for an
object (also known as "colourhax") from the editor UI, I stumble upon
these wretched ternary items again and sigh a deep sigh of annoyance.
The structure is overly rigid. `TernaryItem` does nothing that
`DrawableTernaryItem` couldn't, except make it more annoying to add
specific sub-variants of `DrawableTernaryItem` that could do more
things.
Yes you could sprinkle more levels of virtuals to
`CreateDrawableButton()` or something, but after all, as Saint Exupéry
says, "perfection is finally attained not when there is no longer
anything to add, but when there is no longer anything to take away."
So I'm leaning for taking one step towards perfection.
Regressed in https://github.com/ppy/osu/pull/25171.
The old code was kinda dependent on correct order of setting `Disabled`.
`CatchHitObjectComposer` would disable distance spacing in its BDL, and
then via the base `DistancedHitObjectComposer.LoadComplete()`, the
slider would be faded out. The switch to composition broke that
ordering.
To fix, stop relying on ordering and just respond to changes as they
come. That's what bindables are for.
