Custom data edited via quick update does not add to changelog

Summary

Updating a contact's custom field data via the quick edit admin UI does not add a changelog, and therefore does not update the 'Last updated' date of the contact. If updated via the API, or by clicking 'Edit' on a contact, it does.

Steps to recreate on dmaster.demo

• Create a new custom fieldset used for contacts, with two fields: 'Custom text' (alphanum, text)
• View a contact record, note the 'Changelog' number, and the last updated date
• Update only the 'Custom text' field on the contact record via the JavaScript interface (click on the field, add data, save)
• Note that there is no changelog, and no change in 'Last updated' date

• Now click 'Edit' on the contact record
• Change only the 'Cutsom text' field
• Save
• Note that there is a changelog, and the 'Last updated' date has updated

Related?
CRM-11854
CRM-10479