fix(combo): selectable unique falsy values #11610

[kdinev]

Closes #11610
Related #10952

** NOTE FOR TESTING **: Please verify that the scenario in this conversation is also covered by the fix!

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[wnvko]

should we make this work and with array of primitive values, e.g. combo.data = [ null, false, true, '', 0, undefined]?

[kdinev]

@wnvko I would say not really. Those values don't have meaningful display representation to the end-user, so I don't consider this to be a real scenario that we should support.