MW 1.35: Re-add class attribute for ULS

Without the class attribute, the ULS does not open on MW <= 1.35.
This was changed in Ie9e30af5468aea9803d77c9a36e480ba2b2e86a0

Bug: T294021
Change-Id: I1bcf4e442e85f8848c5e4ff5609204602265b949

includes/UniversalLanguageSelectorHooks.php

@@ -220,18 +220,30 @@ class UniversalLanguageSelectorHooks {
 
 		// The element id will be 'pt-uls'
 		$langCode = $context->getLanguage()->getCode();
-		return [
-			'uls' => [
-				'text' => Language::fetchLanguageName( $langCode ),
-				'href' => '#',
-				// Skin meta data to allow skin (e.g. Vector) to add icons
-				'icon' => 'wikimedia-language',
-				// Skin meta data to allow skin (e.g. Vector) to convert to button.
-				'button' => true,
-				'link-class' => [ 'uls-trigger' ],
-				'active' => true
-			]
-		] + $personal_urls;
+
+		if ( version_compare( MW_VERSION, '1.36', '<' ) ) {
+			return [
+				'uls' => [
+					'text' => Language::fetchLanguageName( $langCode ),
+					'href' => '#',
+					'class' => 'uls-trigger',
+					'active' => true
+				]
+			] + $personal_urls;
+		} else {
+			return [
+				'uls' => [
+					'text' => Language::fetchLanguageName( $langCode ),
+					'href' => '#',
+					// Skin meta data to allow skin (e.g. Vector) to add icons
+					'icon' => 'wikimedia-language',
+					// Skin meta data to allow skin (e.g. Vector) to convert to button.
+					'button' => true,
+					'link-class' => [ 'uls-trigger' ],
+					'active' => true
+				]
+			] + $personal_urls;
+		}
 	}
 
 	/**