document.on.contentLoaded and document.on.readyStateChanged events not getting called.

[DartBot]

This issue was originally filed by liehan...@google.com

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window.on.contentLoaded works as a workaround.

import('dart:html', prefix: "html");

void main() {
  html.document.on.contentLoaded.add((e) {
    print('no joy');
  });
}
 

[DartBot]

This comment was originally written by mattsh@google.com

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Added Duplicate label.
Marked as being merged into #619.