[web/data] Ignore disabled widgets in cw.utils.formContents() (closes #3544492)
17.12.1 Disabled controls : http://www.w3.org/TR/REC-html40/interact/forms.html#h-17.12.1
When set, the disabled attribute has the following effects on an element:
* Disabled controls do not receive focus.
* Disabled controls are skipped in tabbing navigation.
* Disabled controls cannot be successful.
The third one is the important one.
17.13.2 Successful controls : http://www.w3.org/TR/REC-html40/interact/forms.html#successful-controls
A successful control is "valid" for submission. Every successful control has
its control name paired with its current value as part of the submitted form
data set.
Bottom line, disable widgets should not be part of the names and values lists returned by formContents().