chromium/chrome/test/data/password/multi_frames.html

<html>
<body>

<iframe src="done.html" id="no_form_frame" name="no_form_frame">
</iframe>
<iframe src="password_form.html" id="first_frame" name="first_frame">
</iframe>
<iframe src="password_form.html" id="second_frame" name="second_frame">
</iframe>

<form method="POST" action="done.html" onsubmit="return false;" id="testform">
  <input type="text" id="username_field" name="username_field">
  <input type="password" id="password_field" name="password_field">
  <input type="submit" id="input_submit_button" name="input_submit_button">
</form>

<form method="POST" action="multi_frames.html" id="to_multi_frames">
  <input type="text" id="username_failed" name="username_failed">
  <input type="password" id="password_failed" name="password_failed">
  <input type="submit" id="submit_failed" name="submit_failed">
</form>

</body>
</html>