Fixed the behaviour of form submit to match the standard: no submit is taken place when the form is detached from the document (e.g., form is removed).
One additional layout test (form-removed-from-document.html) is added to verify the change made above.
Two layout tests has been modified to match the behaviour of submitting form (when from is detached from/attached to the document) in Firefox.
BUG=586749
Review-Url: https://codereview.chromium.org/2416033002
Cr-Commit-Position: refs/heads/master@{#425734}
8 files changed
