Fix a log warning when searching for ranges on custom "Date" fields

Summary:
See <https://discourse.phabricator-community.org/t/traceback-rendering-task-query-in-dashboard/2450/>.

It looks like this blames to D19126, which added some more complex constraint logic but overlooked "range" constraints, which are handled separately.

Test Plan:
  - Added a custom "date" field to Maniphest with `"search": true`.
  - Executed a range query against the field.

Then:

  - Before: Warnings about undefined indexes in the log.
  - After: No such warnings.

Reviewers: amckinley

Reviewed By: amckinley

Subscribers: jbrownEP

Differential Revision: https://secure.phabricator.com/D20225

src/infrastructure/query/policy/PhabricatorCursorPagedPolicyAwareQuery.php

@@ -1233,6 +1233,8 @@ abstract class PhabricatorCursorPagedPolicyAwareQuery
       'index' => $index->getIndexKey(),
       'alias' => $alias,
       'value' => array($min, $max),
+      'data' => null,
+      'constraints' => null,
     );
 
     return $this;