Weird problem when passing borrowed C as type argument

[dlongnecke-cray]

Summary of Problem

When I pass the type borrowed C to a function and then instantiate the type argument using new, I expect an instance of a borrowed C but get an owned C.

Steps to Reproduce

Source Code:

class C { var x: int = 0; }

proc test(type t) {
  var x = new t(128);
  compilerWarning(x.type:string);
  return;
}
type t = borrowed C?;
test(t);

[dlongnecke-cray]

Discussion about this started in #15394.

Here's a copy of a post I made there earlier...

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It's clear that the decorator is there and then is being ignored, though...

class C { var x: int = 0; }

proc test(type t) {
  var x = new borrowed t(128);
  compilerWarning(x.type:string);
  return;
}
type T = borrowed C?;
test(T);

TestPassedBorrow.chpl:3: In function 'test':
TestPassedBorrow.chpl:4: error: duplicate decorators - borrowed borrowed C?
TestPassedBorrow.chpl:9: Function 'test' instantiated as: test(type t = borrowed C?)
TestPassedBorrow.chpl:9: warning: borrowed C?

If the class didn't have a decorator attached to it I would expect an implicit owned. But when it already has a borrowed, seems weird to just discard it.