Import dependencies to make unit tests friendlier to running independ…

…ently

The HHVM test runner runs the unit tests in parallel. Currently some tests
fail because not all the dependencies are properly included.

Signed-off-by: Jeff Chan <jefftchan@gmail.com>

test/libraries/PMA_Tracker_test.php

@@ -11,6 +11,7 @@
  */
 require_once 'libraries/Tracker.class.php';
 require_once 'libraries/DatabaseInterface.class.php';
+require_once 'libraries/database_interface.inc.php';
 require_once 'libraries/Util.class.php';
 require_once 'libraries/php-gettext/gettext.inc';
 require_once 'libraries/relation.lib.php';