Depth is not consistently increased

[bakkot]

E.g.

Function nodes only have depth increased when entering their bodies, which is not consistent with everything else.

[michaelficarra]

Should enterFunction implicitly goDeeper?

[bakkot]

That was the original plan, but was changed because enterFunction must be called after generating the name of a method (to e.g. avoid generating the program ({ [new.target](){} }). It's probably better for every complex node fuzzer (i.e. not just ap) to call goDeeper as its first statement.