Fix Bug 39535 Recent languages in languages settings

* Refactor the code for frequent languages and introduce
  mw.uls.getFrequentLanguageList
* Use it for showing previous languages in language settings
* Show the frequent/common language list in the language selector
  opened from display settings.

Change-Id: Ic0f8ea6b9e9ba137b22649e8425fce8014ad456c

lib/jquery.uls/src/jquery.uls.lcd.js

@@ -141,9 +141,6 @@
 			// Pick only the first elements, because we don't have room for more
 			var that = this,
 				quickList = this.options.quickList;
-			quickList = $.grep( quickList, function( langCode, index ) {
-				return that.options.languages[langCode];
-			} );
 			quickList = quickList.slice( 0, 16 );
 			quickList.sort( $.uls.data.sortByAutonym );
 			var $quickListsection = $( '<div>' ).addClass( 'twelve columns uls-lcd-region-section' ).prop( 'id', 'uls-lcd-quicklist' );

resources/js/ext.uls.displaysettings.js

@@ -103,7 +103,7 @@
 			var that = this;
 			var $languages = this.$template.find( 'div.uls-ui-languages' );
 			$languages.empty();
-			var previousLanguages = this.previousLanguages();
+			var previousLanguages = this.frequentLanguageList();
 			var languages = [this.uiLanguage];
 			for ( var lang in previousLanguages ) {
 				if ( previousLanguages[lang] === this.uiLanguage ) {
@@ -169,6 +169,9 @@
 					that.$parent.show();
 					that.prepareUIFonts();
 					that.prepareLanguages();
+				},
+				quickList: function() {
+					return mw.uls.getFrequentLanguageList();
 				}
 			} );
 
@@ -181,9 +184,8 @@
 		 * Get previous languages
 		 * @returns {Array}
 		 */
-		previousLanguages: function () {
+		frequentLanguageList: function () {
-			// FIXME
+			return mw.uls.getFrequentLanguageList();
-			return [ $.cookie( 'uls-previous-language' ) || 'he', 'hi', 'ml', 'ta'];
 		},
 
 		/**

resources/js/ext.uls.init.js

@@ -63,6 +63,28 @@
 		return mw.config.get( "wgULSAcceptLanguageList" );
 	};
 
+	mw.uls.getFrequentLanguageList = function() {
+		var unique = [],
+			list = [ mw.config.get( 'wgUserLanguage' ),
+				mw.config.get( 'wgContentLanguage' ),
+				mw.uls.getBrowserLanguage() ]
+				.concat( mw.uls.getPreviousLanguages() )
+				.concat( mw.uls.getAcceptLanguageList() );
+		if ( window.GEO ) {
+			list = list.concat( $.uls.data.languagesInTerritory( window.GEO.country_code ) );
+		}
+		$.each( list, function( i, v ) {
+			if ( $.inArray( v, unique ) === -1 ) {
+				unique.push( v );
+			}
+		} );
+		// Filter out unknown and unsupported languages
+		unique = $.grep( unique, function( langCode, index ) {
+			return $.fn.uls.defaults.languages[langCode];
+		} );
+		return unique;
+	};
+
 	$( document ).ready( function() {
 		var $ulsTrigger = $( '.uls-trigger' ),
 			previousLanguages = mw.uls.getPreviousLanguages() || [],
@@ -106,23 +128,7 @@
 			languages: mw.config.get( 'wgULSLanguages' ),
 			searchAPI: mw.util.wikiScript( 'api' ) + "?action=languagesearch",
 			quickList: function() {
-				var unique = [],
+				return mw.uls.getFrequentLanguageList();
-					list = [
-						mw.config.get( 'wgUserLanguage' ),
-						mw.config.get( 'wgContentLanguage' ),
-						mw.uls.getBrowserLanguage()
-					]
-					.concat( mw.uls.getPreviousLanguages() )
-					.concat( mw.uls.getAcceptLanguageList() );
-				if ( window.GEO ) {
-					list = list.concat( $.uls.data.languagesInTerritory( window.GEO.country_code ) );
-				}
-				$.each( list, function ( i, v ) {
-					if ( $.inArray( v, unique ) === -1 ) {
-						unique.push( v );
-					}
-				} );
-				return unique;
 			}
 		} );