uniform use of Document_View.robust_body;

merged

merge

fixed soundness bug made more visible by previous change

use more appropriate type systems for ATP exporter

type arguments now (unlike back when fa2cf11d6351 was done) normally carry enough information to reconstruct the type of an applied constant, so no need to constraint the argument types in those cases

more robust painter_body wrt. EBP races and spurious exceptions (which causes jEdit to remove the extension);