R1:5729bbc085f2

Fix transaction comment bug

Summary: form.reset() resets a form to whatever values were present when the form was loaded into the DOM. Instead, grab all the pertinent form bits and set there values to "clear". I don't think there's too much utility in putting this somewhere more general, but it could be something like DOM.clearForm(form) or something. Fixes T3629.

Test Plan:
repro'd original issue

- open legalpad doc (or your favorite application transaction powered app)
- type in a comment but do not…