Where did `inSpan''` go?

[ocharles]

We used to have a version of inSpan'' that took an explicit CallStack. However, in 0.1 inSpan'' no longer takes a CallStack (and seems to be identical to the type of inSpan'). Is this intentional? If so, what should I do if I have a CallStack I want to use instead of using whatever HasCallstack has?