5 calls to drupal_maintenance_theme()

authorize.php in ./authorize.php
Administrative script for running authorized file operations.
drupal_deliver_html_page in includes/common.inc
Packages and sends the result of a page callback to the browser as HTML.
install_begin_request in includes/install.core.inc
Begins an installation request, modifying the installation state as needed.
update.php in ./update.php
Administrative page for handling updates from one Drupal version to another.
_drupal_log_error in includes/errors.inc
Logs a PHP error or exception and displays an error page in fatal cases.

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