[css-values-5] Should we keep the single-argument form of calc-size() #10478
Description
As discussed in #10294 (comment) I think we should be recommending the new interpolate-size property as the mechanism for opting in to using interpolation of sizing keywords via calc-size().
calc-size() currently has a single-argument form that I think was designed to make it easy to opt an animation endpoint in to this interpolation by wrapping it with calc-size(). However, as that comment explains, I don't think we should recommend this form of opting in because of its effects on non-supporting engines during the period when the feature is implemented in some but not "all" engines.
This then leads to the question: should we still have the single-argument form of calc-size() at all? Or should we drop it?
cc @tabatkins