Inconsistent handling of UFField.visbility in profile editor

The profile editor includes some sugar to ensure that 'is_searchable' and 'visibility' make sense – if a UFGroup has "Used For: [x] Search Views", then CRM_UF_Form_Field only allows UFField.visibility to be set to "Public Pages and Listings". However, this is buggy – consider the sequence:

1) Create new UFGroup with "[ ] Search Views" disabled
2) Add UFField with visibility "User..."
3) Edit UFGroup to enable "[x] Search Views"
4) Edit UFField. At this point, the DB says the UFField has visibility "User" but the UI says "Public Pages and Listings".

Proposed solutions:
a) Remove the current sugary behavior
b) Make the sugary behavior consistent: When an admin saves a UFGroup with the "[x] Search Views" enabled, automatically scan for UFFields which have incorrect visibility. Alert the admin and fix the UFField visibilities. (Note: Alerting the admin is necessary to mitigate an unintuitive consequence of this fix. The consequence is that, if an admin enables and then disables "[x] Search Views", then all the underlying fields will be unnecessarily changed.)

See also: http://issues.civicrm.org/jira/browse/CRM-11493?focusedCommentId=47565