Simplify the internal API of clearing functions in Equality.
Simplify the internal API of clearing functions in Equality.

We only care about the fact that a term might be a variable, so we pass this
around statically.

SkySkimmer/coq,ejgallego/coq,Zimmi48/coq,SkySkimmer/coq,ejgallego/coq,coq/coq,SkySkimmer/coq,Zimmi48/coq,Zimmi48/coq,SkySkimmer/coq,coq/coq,coq/coq,ejgallego/coq,ejgallego/coq,coq/coq,Zimmi48/coq