$reader: XMLReader object
$revisionInfo: Array of information
+'ImportSources': Called when reading from the $wgImportSources configuration
+variable. Can be used to lazy-load the import sources list.
+&$importSources: The value of $wgImportSources. Modify as necessary. See the
+comment in DefaultSettings.php for the detail of how to structure this array.
+
'InfoAction': When building information to display on the action=info page.
$context: IContextSource object
&$pageInfo: Array of information