Warning 337 does not produce a line number in the language server

[briangmilnes]

If you foolishly add a decreases to an interface you get a 337 but in the language server
it does not give you a line number. Perhaps a sweep of all warnings in the compiler
for this difference should be quickly performed also.
FSTI:
module MultipleDecreases
val length #a (l:list a) : Tot nat (decreases l)
module MultipleDecreases

let rec length #a (l:list a)
: Tot nat (decreases l)
= match l with
| [] -> 0
| _ :: tl -> length tl

// In the language server no line is produced
//(Warning 337) - This definitions has multiple decreases clauses.
//- The decreases clause on the declaration is ignored, please remove it.
// In the compiler the error has a line
//qqmake -k validate
//Forge: VALIDATE _build/fstar/fst/checked directory
//Forge: VALIDATE make -k _build/fstar/fst/checked/MultipleDecreases.fsti.checked //_build/fstar/fst/checked/MultipleDecreases.fst.checked PROJECT=multipledecreases
//Forge: VALIDATE _build/fstar/fst/checked/MultipleDecreases.fsti.checked
//Forge: VALIDATE _build/fstar/fst/checked/MultipleDecreases.fst.checked
//* Warning 337 at src/MultipleDecreases.fst(3,8-3,14):
// - This definitions has multiple decreases clauses.