Fix: Adapt datpicker.js for a11y

ui/widgets/datepicker.js

@@ -99,7 +99,9 @@ function Datepicker() {
 		firstDay: 0, // The first day of the week, Sun = 0, Mon = 1, ...
 		isRTL: false, // True if right-to-left language, false if left-to-right
 		showMonthAfterYear: false, // True if the year select precedes month, false for month then year
-		yearSuffix: "" // Additional text to append to the year in the month headers
+		yearSuffix: "", // Additional text to append to the year in the month headers,
+		selectMonthLabel: "Select month", // Invisible label for month selector
+		selectYearLabel: "Select year" // Invisible label for year selector
 	};
 	this._defaults = { // Global defaults for all the date picker instances
 		showOn: "focus", // "focus" for popup on focus,
@@ -1910,7 +1912,8 @@ $.extend( Datepicker.prototype, {
 							( printDate.getTime() === today.getTime() ? " ui-state-highlight" : "" ) +
 							( printDate.getTime() === currentDate.getTime() ? " ui-state-active" : "" ) + // highlight selected day
 							( otherMonth ? " ui-priority-secondary" : "" ) + // distinguish dates from other months
-							"' href='#'>" + printDate.getDate() + "</a>" ) ) + "</td>"; // display selectable date
+							"' href='#' aria-current='" + ( printDate.getTime() === currentDate.getTime() ? "true" : "false" ) + // mark date as selected for screen reader
+							"'>" + printDate.getDate() + "</a>" ) ) + "</td>"; // display selectable date
 						printDate.setDate( printDate.getDate() + 1 );
 						printDate = this._daylightSavingAdjust( printDate );
 					}
@@ -1940,6 +1943,8 @@ $.extend( Datepicker.prototype, {
 			changeMonth = this._get( inst, "changeMonth" ),
 			changeYear = this._get( inst, "changeYear" ),
 			showMonthAfterYear = this._get( inst, "showMonthAfterYear" ),
+			selectMonthLabel = this._get( inst, "selectMonthLabel" ),
+			selectYearLabel = this._get( inst, "selectYearLabel" ),
 			html = "<div class='ui-datepicker-title'>",
 			monthHtml = "";
 
@@ -1949,7 +1954,7 @@ $.extend( Datepicker.prototype, {
 		} else {
 			inMinYear = ( minDate && minDate.getFullYear() === drawYear );
 			inMaxYear = ( maxDate && maxDate.getFullYear() === drawYear );
-			monthHtml += "<select class='ui-datepicker-month' data-handler='selectMonth' data-event='change'>";
+			monthHtml += "<select class='ui-datepicker-month' aria-label='" + selectMonthLabel + "' data-handler='selectMonth' data-event='change'>";
 			for ( month = 0; month < 12; month++ ) {
 				if ( ( !inMinYear || month >= minDate.getMonth() ) && ( !inMaxYear || month <= maxDate.getMonth() ) ) {
 					monthHtml += "<option value='" + month + "'" +
@@ -1984,7 +1989,7 @@ $.extend( Datepicker.prototype, {
 				endYear = Math.max( year, determineYear( years[ 1 ] || "" ) );
 				year = ( minDate ? Math.max( year, minDate.getFullYear() ) : year );
 				endYear = ( maxDate ? Math.min( endYear, maxDate.getFullYear() ) : endYear );
-				inst.yearshtml += "<select class='ui-datepicker-year' data-handler='selectYear' data-event='change'>";
+				inst.yearshtml += "<select class='ui-datepicker-year' aria-label='" + selectYearLabel + "' data-handler='selectYear' data-event='change'>";
 				for ( ; year <= endYear; year++ ) {
 					inst.yearshtml += "<option value='" + year + "'" +
 						( year === drawYear ? " selected='selected'" : "" ) +