Map calc() constant tests to web-features

[foolip]

[foolip]

@jcscottiii I've left this in draft because it's not possible to map the tests well enough IMHO. There are standalone tests for infinity and nan, but the tests for e and pi are part of the tests for exponential and trigonometric functions, respectively.

The easiest way to unblock this would be to add simpler tests that just test the constants, like calc(e) and calc(pi). That just needs some unitless-number-accepting property to test it on. @danielsakhapov do you know of such a property?

[danielsakhapov]

I think scale should work