Dialog: Escape closeText option before passing it to button

Ref gh-1632
Fixes jquery/api.jqueryui.com#281

Author: jzaefferer

tests/unit/dialog/options.js

@@ -206,7 +206,7 @@ test( "closeOnEscape", function() {
 } );
 
 test( "closeText", function() {
-	expect( 3 );
+	expect( 4 );
 
 	var element = $( "<div></div>" ).dialog();
 		equal( $.trim( element.dialog( "widget" ).find( ".ui-dialog-titlebar-close" ).text() ), "Close",
@@ -222,6 +222,11 @@ test( "closeText", function() {
 		equal( $.trim( element.dialog( "widget" ).find( ".ui-dialog-titlebar-close" ).text() ), "bar",
 			"closeText via option method" );
 	element.remove();
+
+	element = $( "<div></div>" ).dialog( { closeText: "<span>foo</span>" } );
+		equal( $.trim( element.dialog( "widget" ).find( ".ui-dialog-titlebar-close" ).text() ), "<span>foo</span>",
+			"closeText is escaped" );
+	element.remove();
 } );
 
 test( "draggable", function() {

ui/widgets/dialog.js

@@ -426,7 +426,7 @@ $.widget( "ui.dialog", {
 		// dialog in IE (#9312)
 		this.uiDialogTitlebarClose = $( "<button type='button'></button>" )
 			.button( {
-				label: this.options.closeText,
+				label: $( "<a>" ).text( this.options.closeText ).html(),
 				icon: "ui-icon-closethick",
 				showLabel: false
 			} )
@@ -715,7 +715,7 @@ $.widget( "ui.dialog", {
 			this.uiDialogTitlebarClose.button( {
 
 				// Ensure that we always pass a string
-				label: "" + value
+				label: $( "<a>" ).text( "" + this.options.closeText ).html()
 			} );
 		}