KeyCombo Modifiers Setter

[bdkjones]

Compiling with Xcode 11.4.1 yields this warning in keyCombo.swift:

I've looked at the source for all of twenty seconds, but it seems like this setter is never going to set anything new. If that's intentional, should this setter exist? If this exists for a reason, perhaps a comment to explain why or silencing the warning would be handy?