INPUT element: Do not dispatch events in detachLayoutTree().
When a color chooser is closed, we dispatches a 'change' event asynchronously.
Some tests need to be updated due to this behavior change.
BUG=
658535
Committed:
https://crrev.com/fbe37c7239e4a6e75f12c0d35e60987a6aa75ee0
Cr-Commit-Position: refs/heads/master@{#427286}