Scroll language settings on all changes

Change-Id: I550f309d713cb6aac6b18b326379b879dc0b9589

resources/js/ext.uls.languagesettings.js

@@ -96,10 +96,11 @@
 		 * @param active boolean Make this module active and show by default
 		 */
 		renderModule: function ( moduleName, active ) {
-			var $settingsMenuItems, module, $settingsText, $settingsTitle, $settingsLink;
+			var $settingsMenuItems, module, $settingsText, $settingsTitle, $settingsLink,
+				languageSettings = this;
 
-			$settingsMenuItems = this.$window.find( '.settings-menu-items' );
-			module = new $.fn.languagesettings.modules[moduleName]( this );
+			$settingsMenuItems = languageSettings.$window.find( '.settings-menu-items' );
+			module = new $.fn.languagesettings.modules[moduleName]( languageSettings );
 			$settingsTitle = $( '<div>' )
 				.addClass( 'settings-title' )
 				.text( module.name );
@@ -116,8 +117,38 @@
 			$settingsMenuItems.append( $settingsLink );
 
 			$settingsLink.on( 'click', function () {
-				var module = $( this ).data( 'module' );
+				var scrollPosition,
+					panelHeight, panelTop, panelBottom,
+					padding = 10,
+					$window = $( window ),
+					windowHeight = $window.height(),
+					windowScrollTop = $window.scrollTop(),
+					windowBottom = windowScrollTop + windowHeight,
+					module = $( this ).data( 'module' );
+
 				module.render();
+
+				panelHeight = languageSettings.$window.height();
+				panelTop = languageSettings.$window.offset().top;
+				panelBottom = panelTop + panelHeight;
+
+				// If the ULS panel is out of the viewport,
+				// scroll the window to show it
+				if ( ( panelTop < windowScrollTop ) || ( panelBottom > windowBottom ) ) {
+					if ( panelHeight > windowHeight ) {
+						// Scroll to show as much of the upper
+						// part of ULS as possible
+						scrollPosition = panelTop - padding;
+					} else {
+						// Scroll just enough to show the ULS panel
+						scrollPosition = panelBottom - windowHeight + padding;
+					}
+
+					$( 'html, body' ).stop().animate( {
+						scrollTop: scrollPosition
+					}, 500 );
+				}
+
 				$settingsMenuItems.find( '.menu-section' ).removeClass( 'active' );
 				$( this ).addClass( 'active' );
 			} );