In #32656 I generalized the argument to change selections to allow
controling both the scroll and the nav history (and the completion
trigger).
To avoid conflicting with ongoing debugger cherry-picks I left the
argument as an `impl Into<>`, but I think it's clearer to make callers
specify what they want here.
I converted a lot of `None` arguments to `SelectionEffects::no_scroll()`
to be exactly compatible; but I think many people used none as an "i
don't care" value in which case Default::default() might be more
appropraite
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