When binding to form inputs' valueChanges observable, methods attached to elements will trigger valueChanges to fire unexpectedly.

Reproduction: http://plnkr.co/edit/aBvtMSfBsSZcAH83GUjN?p=preview
Steps:

• Type in input box, observe valueChanges observable logging values (expected).
• Click button (which is outside of form) - observe observable logging values (unexpected)

cc @vsavkin