Upstreaming from https://phabricator.wikimedia.org/T217984
**Steps to reproduce:**
1. Phorge at `428f9686c4171912ee186ebd919640a7427da768`, PHP 8.2.14
2. Go to http://phorge.localhost/maniphest/query/advanced/
3. Set "Closed By" to "Current Viewer" and Search.
4. Copy the resulting query URL
5. Open that URL in an incognito browser window without being logged into Phorge (thus: "Current Viewer" is not set).
**Expected results:**
An error message which allows the user to potentially understand what went wrong, and allows them to correct.
**Actual results:**
```
This datasource ("PhabricatorPeopleUserFunctionDatasource") can not evaluate the function "viewer(...)".
Depth Library File Where
27 phorge applications/typeahead/datasource/PhabricatorTypeaheadDatasource.php : 280 PhabricatorTypeaheadDatasource::parseFunction()
26 phorge view/form/control/AphrontFormTokenizerControl.php : 76 PhabricatorTypeaheadDatasource::renderTokens()
25 phorge view/form/control/AphrontFormControl.php : 183 AphrontFormTokenizerControl::renderInput()
24 phorge view/AphrontView.php : 222 AphrontFormControl::render()
23 phorge infrastructure/markup/render.php : 115 AphrontView::producePhutilSafeHTML()
```
== Proposal n. 1 ==
If login is required, just redirect to the login form instead of crashing.
== Proposal n. 2 ==