Advanced search: can no longer search for contacts named X involved in activities assigned to Y

In 4.3 and prior, you could enter a name in the main name field on the advanced search and then, under the activities section, click Created By or Assigned To and enter a different contact's name. The result would be all contacts named X involved in activities that were assigned to a contact named Y. Entering "%" in the main name field at the top would find everyone involved in those activities.

The use case is to find, for example, all the clients who had meetings with a particular social worker or the donors named Jones who had phone calls with a particular staff member.

Now, as of 4.4, the extra field has been removed, and this is no longer possible. Although not everyone used this feature, some organizations rely on it heavily, and there is no other way to get that set of results.