(Regression) Cannot add more than one "phone" field to Profile form

Beginning in 2.1.6, CiviCRM will not allow an administrator to create a Profile with more than one phone number field.

Steps to reproduce:

• Open "Administer CiviCRM"
• Create a new profile
• Add a new field with field name "Contact -> Phone -> Home -> Phone". Press "Save". This succeeds.
• Add a new field with field name "Contact -> Phone -> Home -> Mobile". Press "Save". This fails with message "The selected field was not added. It already exists in this profile."

The regression was introduced by r19144:

http://fisheye.civicrm.org/changelog/CiviCRM?cs=19144

Specifically, "$ufField->phone_type_id" should be "$ufField->phone_type", as documented in:

http://fisheye.civicrm.org/browse/CiviCRM/trunk/xml/schema/Core/UFField.xml