Google Code-in

With the following configuration in your LocalSettings.php file:

$wgImportSources = array(
    'first',
    'second' => array( 'eee', 'aaa', 'bbb' ),
    'third' => array( 'eee', 'aaa', 'bbb' ),
    'fourth',
);

you will notice that when you switch the dropdown on Special:Import from "first" to "second", the entry "aaa" is selected initially. This is incorrect. The first entry in the list should be selected initially. Your task is to investigate and fix this bug.

Relevant JavaScript code is located in resources/src/mediawiki.special/mediawiki.special.import.js in the mediawiki/core Git repository. Read https://www.mediawiki.org/wiki/Gerrit for more details on submitting your code and the review process.