Wrong compile output with non top level element selector followed by new line comment.

[suienzan]

To reproduce:

@-moz-document domain("www.google.com") {
  body, 
  // comment
  .class {
    background: #000;
  }
}

Current behavior:

compile output

@-moz-document domain("www.google.com") {
  body: ,;
  .class {
    background: #000;
  }
}

Expected behavior:

output

@-moz-document domain("www.google.com") {
  body,
  .class {
    background: #000;
  }
}

Environment information:

• stylus version: https://stylus-lang.com/try.html

demo1 and demo2.

openstyles/stylus#1460