For support of cross-origin iframes in Autofill and Password Manager messaging framework should be implemented. Details are in go/bling-iframe-injection.
form.js implements form/input event handlers. Now injected functions from the main frame are called in form.js. It works for iframes with the same origin as the main frame, but it wouldn't work for cross-origin iframes. When messaging framework is implemented, sending messages should be implemented for cross-origin support.
Comment 1 by ma...@chromium.org
, May 1 2018