Load ULS language list from a resource loader module

Having them in the page source of every page view is wasteful.

Bug: 41210
Change-Id: If15e297a4781cc49ded06fbc906529f57a22aafe

UniversalLanguageSelector.hooks.php

@@ -281,9 +281,6 @@ class UniversalLanguageSelectorHooks {
 	 */
 	public static function addVariables( &$vars, OutputPage $out ) {
 		// Place request context dependent stuff here
-		$vars['wgULSLanguages'] = Language::fetchLanguageNames(
-			$out->getLanguage()->getCode(), 'mwfile'
-		);
 		$vars['wgULSAcceptLanguageList'] = array_keys( $out->getRequest()->getAcceptLang() );
 
 		return true;