Missing new keyword

[nshahan]

Missing a "new" keyword on an external constructor.

A call to:

@JS('Quill')
abstract class QuillStatic {
  external factory QuillStatic(String selector, [QuillOptionsStatic options]);
...
}
external QuillStatic get Quill;

produced the javasctip code:

main.bar = dart.global.Quill('#editor', {theme: 'snow', placeholder: main.prompt});

[kevmoo]

Fix pending - https://codereview.chromium.org/2399593003/