diff -r 34716fd837a4 -r be944660c56a wp/wp-includes/js/jquery/ui/dialog.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/js/jquery/ui/dialog.js	Wed Sep 21 18:19:35 2022 +0200
@@ -0,0 +1,932 @@
+/*!
+ * jQuery UI Dialog 1.12.1
+ * http://jqueryui.com
+ *
+ * Copyright jQuery Foundation and other contributors
+ * Released under the MIT license.
+ * http://jquery.org/license
+ */
+
+//>>label: Dialog
+//>>group: Widgets
+//>>description: Displays customizable dialog windows.
+//>>docs: http://api.jqueryui.com/dialog/
+//>>demos: http://jqueryui.com/dialog/
+//>>css.structure: ../../themes/base/core.css
+//>>css.structure: ../../themes/base/dialog.css
+//>>css.theme: ../../themes/base/theme.css
+
+( function( factory ) {
+	if ( typeof define === "function" && define.amd ) {
+
+		// AMD. Register as an anonymous module.
+		define( [
+			"jquery",
+			"./button",
+			"./draggable",
+			"./mouse",
+			"./resizable",
+			"./core"
+		], factory );
+	} else {
+
+		// Browser globals
+		factory( jQuery );
+	}
+}( function( $ ) {
+
+$.widget( "ui.dialog", {
+	version: "1.12.1",
+	options: {
+		appendTo: "body",
+		autoOpen: true,
+		buttons: [],
+		classes: {
+			"ui-dialog": "ui-corner-all",
+			"ui-dialog-titlebar": "ui-corner-all"
+		},
+		closeOnEscape: true,
+		closeText: "Close",
+		draggable: true,
+		hide: null,
+		height: "auto",
+		maxHeight: null,
+		maxWidth: null,
+		minHeight: 150,
+		minWidth: 150,
+		modal: false,
+		position: {
+			my: "center",
+			at: "center",
+			of: window,
+			collision: "fit",
+
+			// Ensure the titlebar is always visible
+			using: function( pos ) {
+				var topOffset = $( this ).css( pos ).offset().top;
+				if ( topOffset < 0 ) {
+					$( this ).css( "top", pos.top - topOffset );
+				}
+			}
+		},
+		resizable: true,
+		show: null,
+		title: null,
+		width: 300,
+
+		// Callbacks
+		beforeClose: null,
+		close: null,
+		drag: null,
+		dragStart: null,
+		dragStop: null,
+		focus: null,
+		open: null,
+		resize: null,
+		resizeStart: null,
+		resizeStop: null
+	},
+
+	sizeRelatedOptions: {
+		buttons: true,
+		height: true,
+		maxHeight: true,
+		maxWidth: true,
+		minHeight: true,
+		minWidth: true,
+		width: true
+	},
+
+	resizableRelatedOptions: {
+		maxHeight: true,
+		maxWidth: true,
+		minHeight: true,
+		minWidth: true
+	},
+
+	_create: function() {
+		this.originalCss = {
+			display: this.element[ 0 ].style.display,
+			width: this.element[ 0 ].style.width,
+			minHeight: this.element[ 0 ].style.minHeight,
+			maxHeight: this.element[ 0 ].style.maxHeight,
+			height: this.element[ 0 ].style.height
+		};
+		this.originalPosition = {
+			parent: this.element.parent(),
+			index: this.element.parent().children().index( this.element )
+		};
+		this.originalTitle = this.element.attr( "title" );
+		if ( this.options.title == null && this.originalTitle != null ) {
+			this.options.title = this.originalTitle;
+		}
+
+		// Dialogs can't be disabled
+		if ( this.options.disabled ) {
+			this.options.disabled = false;
+		}
+
+		this._createWrapper();
+
+		this.element
+			.show()
+			.removeAttr( "title" )
+			.appendTo( this.uiDialog );
+
+		this._addClass( "ui-dialog-content", "ui-widget-content" );
+
+		this._createTitlebar();
+		this._createButtonPane();
+
+		if ( this.options.draggable && $.fn.draggable ) {
+			this._makeDraggable();
+		}
+		if ( this.options.resizable && $.fn.resizable ) {
+			this._makeResizable();
+		}
+
+		this._isOpen = false;
+
+		this._trackFocus();
+	},
+
+	_init: function() {
+		if ( this.options.autoOpen ) {
+			this.open();
+		}
+	},
+
+	_appendTo: function() {
+		var element = this.options.appendTo;
+		if ( element && ( element.jquery || element.nodeType ) ) {
+			return $( element );
+		}
+		return this.document.find( element || "body" ).eq( 0 );
+	},
+
+	_destroy: function() {
+		var next,
+			originalPosition = this.originalPosition;
+
+		this._untrackInstance();
+		this._destroyOverlay();
+
+		this.element
+			.removeUniqueId()
+			.css( this.originalCss )
+
+			// Without detaching first, the following becomes really slow
+			.detach();
+
+		this.uiDialog.remove();
+
+		if ( this.originalTitle ) {
+			this.element.attr( "title", this.originalTitle );
+		}
+
+		next = originalPosition.parent.children().eq( originalPosition.index );
+
+		// Don't try to place the dialog next to itself (#8613)
+		if ( next.length && next[ 0 ] !== this.element[ 0 ] ) {
+			next.before( this.element );
+		} else {
+			originalPosition.parent.append( this.element );
+		}
+	},
+
+	widget: function() {
+		return this.uiDialog;
+	},
+
+	disable: $.noop,
+	enable: $.noop,
+
+	close: function( event ) {
+		var that = this;
+
+		if ( !this._isOpen || this._trigger( "beforeClose", event ) === false ) {
+			return;
+		}
+
+		this._isOpen = false;
+		this._focusedElement = null;
+		this._destroyOverlay();
+		this._untrackInstance();
+
+		if ( !this.opener.filter( ":focusable" ).trigger( "focus" ).length ) {
+
+			// Hiding a focused element doesn't trigger blur in WebKit
+			// so in case we have nothing to focus on, explicitly blur the active element
+			// https://bugs.webkit.org/show_bug.cgi?id=47182
+			$.ui.safeBlur( $.ui.safeActiveElement( this.document[ 0 ] ) );
+		}
+
+		this._hide( this.uiDialog, this.options.hide, function() {
+			that._trigger( "close", event );
+		} );
+	},
+
+	isOpen: function() {
+		return this._isOpen;
+	},
+
+	moveToTop: function() {
+		this._moveToTop();
+	},
+
+	_moveToTop: function( event, silent ) {
+		var moved = false,
+			zIndices = this.uiDialog.siblings( ".ui-front:visible" ).map( function() {
+				return +$( this ).css( "z-index" );
+			} ).get(),
+			zIndexMax = Math.max.apply( null, zIndices );
+
+		if ( zIndexMax >= +this.uiDialog.css( "z-index" ) ) {
+			this.uiDialog.css( "z-index", zIndexMax + 1 );
+			moved = true;
+		}
+
+		if ( moved && !silent ) {
+			this._trigger( "focus", event );
+		}
+		return moved;
+	},
+
+	open: function() {
+		var that = this;
+		if ( this._isOpen ) {
+			if ( this._moveToTop() ) {
+				this._focusTabbable();
+			}
+			return;
+		}
+
+		this._isOpen = true;
+		this.opener = $( $.ui.safeActiveElement( this.document[ 0 ] ) );
+
+		this._size();
+		this._position();
+		this._createOverlay();
+		this._moveToTop( null, true );
+
+		// Ensure the overlay is moved to the top with the dialog, but only when
+		// opening. The overlay shouldn't move after the dialog is open so that
+		// modeless dialogs opened after the modal dialog stack properly.
+		if ( this.overlay ) {
+			this.overlay.css( "z-index", this.uiDialog.css( "z-index" ) - 1 );
+		}
+
+		this._show( this.uiDialog, this.options.show, function() {
+			that._focusTabbable();
+			that._trigger( "focus" );
+		} );
+
+		// Track the dialog immediately upon openening in case a focus event
+		// somehow occurs outside of the dialog before an element inside the
+		// dialog is focused (#10152)
+		this._makeFocusTarget();
+
+		this._trigger( "open" );
+	},
+
+	_focusTabbable: function() {
+
+		// Set focus to the first match:
+		// 1. An element that was focused previously
+		// 2. First element inside the dialog matching [autofocus]
+		// 3. Tabbable element inside the content element
+		// 4. Tabbable element inside the buttonpane
+		// 5. The close button
+		// 6. The dialog itself
+		var hasFocus = this._focusedElement;
+		if ( !hasFocus ) {
+			hasFocus = this.element.find( "[autofocus]" );
+		}
+		if ( !hasFocus.length ) {
+			hasFocus = this.element.find( ":tabbable" );
+		}
+		if ( !hasFocus.length ) {
+			hasFocus = this.uiDialogButtonPane.find( ":tabbable" );
+		}
+		if ( !hasFocus.length ) {
+			hasFocus = this.uiDialogTitlebarClose.filter( ":tabbable" );
+		}
+		if ( !hasFocus.length ) {
+			hasFocus = this.uiDialog;
+		}
+		hasFocus.eq( 0 ).trigger( "focus" );
+	},
+
+	_keepFocus: function( event ) {
+		function checkFocus() {
+			var activeElement = $.ui.safeActiveElement( this.document[ 0 ] ),
+				isActive = this.uiDialog[ 0 ] === activeElement ||
+					$.contains( this.uiDialog[ 0 ], activeElement );
+			if ( !isActive ) {
+				this._focusTabbable();
+			}
+		}
+		event.preventDefault();
+		checkFocus.call( this );
+
+		// support: IE
+		// IE <= 8 doesn't prevent moving focus even with event.preventDefault()
+		// so we check again later
+		this._delay( checkFocus );
+	},
+
+	_createWrapper: function() {
+		this.uiDialog = $( "<div>" )
+			.hide()
+			.attr( {
+
+				// Setting tabIndex makes the div focusable
+				tabIndex: -1,
+				role: "dialog"
+			} )
+			.appendTo( this._appendTo() );
+
+		this._addClass( this.uiDialog, "ui-dialog", "ui-widget ui-widget-content ui-front" );
+		this._on( this.uiDialog, {
+			keydown: function( event ) {
+				if ( this.options.closeOnEscape && !event.isDefaultPrevented() && event.keyCode &&
+						event.keyCode === $.ui.keyCode.ESCAPE ) {
+					event.preventDefault();
+					this.close( event );
+					return;
+				}
+
+				// Prevent tabbing out of dialogs
+				if ( event.keyCode !== $.ui.keyCode.TAB || event.isDefaultPrevented() ) {
+					return;
+				}
+				var tabbables = this.uiDialog.find( ":tabbable" ),
+					first = tabbables.filter( ":first" ),
+					last = tabbables.filter( ":last" );
+
+				if ( ( event.target === last[ 0 ] || event.target === this.uiDialog[ 0 ] ) &&
+						!event.shiftKey ) {
+					this._delay( function() {
+						first.trigger( "focus" );
+					} );
+					event.preventDefault();
+				} else if ( ( event.target === first[ 0 ] ||
+						event.target === this.uiDialog[ 0 ] ) && event.shiftKey ) {
+					this._delay( function() {
+						last.trigger( "focus" );
+					} );
+					event.preventDefault();
+				}
+			},
+			mousedown: function( event ) {
+				if ( this._moveToTop( event ) ) {
+					this._focusTabbable();
+				}
+			}
+		} );
+
+		// We assume that any existing aria-describedby attribute means
+		// that the dialog content is marked up properly
+		// otherwise we brute force the content as the description
+		if ( !this.element.find( "[aria-describedby]" ).length ) {
+			this.uiDialog.attr( {
+				"aria-describedby": this.element.uniqueId().attr( "id" )
+			} );
+		}
+	},
+
+	_createTitlebar: function() {
+		var uiDialogTitle;
+
+		this.uiDialogTitlebar = $( "<div>" );
+		this._addClass( this.uiDialogTitlebar,
+			"ui-dialog-titlebar", "ui-widget-header ui-helper-clearfix" );
+		this._on( this.uiDialogTitlebar, {
+			mousedown: function( event ) {
+
+				// Don't prevent click on close button (#8838)
+				// Focusing a dialog that is partially scrolled out of view
+				// causes the browser to scroll it into view, preventing the click event
+				if ( !$( event.target ).closest( ".ui-dialog-titlebar-close" ) ) {
+
+					// Dialog isn't getting focus when dragging (#8063)
+					this.uiDialog.trigger( "focus" );
+				}
+			}
+		} );
+
+		// Support: IE
+		// Use type="button" to prevent enter keypresses in textboxes from closing the
+		// dialog in IE (#9312)
+		this.uiDialogTitlebarClose = $( "<button type='button'></button>" )
+			.button( {
+				label: $( "<a>" ).text( this.options.closeText ).html(),
+				icon: "ui-icon-closethick",
+				showLabel: false
+			} )
+			.appendTo( this.uiDialogTitlebar );
+
+		this._addClass( this.uiDialogTitlebarClose, "ui-dialog-titlebar-close" );
+		this._on( this.uiDialogTitlebarClose, {
+			click: function( event ) {
+				event.preventDefault();
+				this.close( event );
+			}
+		} );
+
+		uiDialogTitle = $( "<span>" ).uniqueId().prependTo( this.uiDialogTitlebar );
+		this._addClass( uiDialogTitle, "ui-dialog-title" );
+		this._title( uiDialogTitle );
+
+		this.uiDialogTitlebar.prependTo( this.uiDialog );
+
+		this.uiDialog.attr( {
+			"aria-labelledby": uiDialogTitle.attr( "id" )
+		} );
+	},
+
+	_title: function( title ) {
+		if ( this.options.title ) {
+			title.text( this.options.title );
+		} else {
+			title.html( "&#160;" );
+		}
+	},
+
+	_createButtonPane: function() {
+		this.uiDialogButtonPane = $( "<div>" );
+		this._addClass( this.uiDialogButtonPane, "ui-dialog-buttonpane",
+			"ui-widget-content ui-helper-clearfix" );
+
+		this.uiButtonSet = $( "<div>" )
+			.appendTo( this.uiDialogButtonPane );
+		this._addClass( this.uiButtonSet, "ui-dialog-buttonset" );
+
+		this._createButtons();
+	},
+
+	_createButtons: function() {
+		var that = this,
+			buttons = this.options.buttons;
+
+		// If we already have a button pane, remove it
+		this.uiDialogButtonPane.remove();
+		this.uiButtonSet.empty();
+
+		if ( $.isEmptyObject( buttons ) || ( $.isArray( buttons ) && !buttons.length ) ) {
+			this._removeClass( this.uiDialog, "ui-dialog-buttons" );
+			return;
+		}
+
+		$.each( buttons, function( name, props ) {
+			var click, buttonOptions;
+			props = $.isFunction( props ) ?
+				{ click: props, text: name } :
+				props;
+
+			// Default to a non-submitting button
+			props = $.extend( { type: "button" }, props );
+
+			// Change the context for the click callback to be the main element
+			click = props.click;
+			buttonOptions = {
+				icon: props.icon,
+				iconPosition: props.iconPosition,
+				showLabel: props.showLabel,
+
+				// Deprecated options
+				icons: props.icons,
+				text: props.text
+			};
+
+			delete props.click;
+			delete props.icon;
+			delete props.iconPosition;
+			delete props.showLabel;
+
+			// Deprecated options
+			delete props.icons;
+			if ( typeof props.text === "boolean" ) {
+				delete props.text;
+			}
+
+			$( "<button></button>", props )
+				.button( buttonOptions )
+				.appendTo( that.uiButtonSet )
+				.on( "click", function() {
+					click.apply( that.element[ 0 ], arguments );
+				} );
+		} );
+		this._addClass( this.uiDialog, "ui-dialog-buttons" );
+		this.uiDialogButtonPane.appendTo( this.uiDialog );
+	},
+
+	_makeDraggable: function() {
+		var that = this,
+			options = this.options;
+
+		function filteredUi( ui ) {
+			return {
+				position: ui.position,
+				offset: ui.offset
+			};
+		}
+
+		this.uiDialog.draggable( {
+			cancel: ".ui-dialog-content, .ui-dialog-titlebar-close",
+			handle: ".ui-dialog-titlebar",
+			containment: "document",
+			start: function( event, ui ) {
+				that._addClass( $( this ), "ui-dialog-dragging" );
+				that._blockFrames();
+				that._trigger( "dragStart", event, filteredUi( ui ) );
+			},
+			drag: function( event, ui ) {
+				that._trigger( "drag", event, filteredUi( ui ) );
+			},
+			stop: function( event, ui ) {
+				var left = ui.offset.left - that.document.scrollLeft(),
+					top = ui.offset.top - that.document.scrollTop();
+
+				options.position = {
+					my: "left top",
+					at: "left" + ( left >= 0 ? "+" : "" ) + left + " " +
+						"top" + ( top >= 0 ? "+" : "" ) + top,
+					of: that.window
+				};
+				that._removeClass( $( this ), "ui-dialog-dragging" );
+				that._unblockFrames();
+				that._trigger( "dragStop", event, filteredUi( ui ) );
+			}
+		} );
+	},
+
+	_makeResizable: function() {
+		var that = this,
+			options = this.options,
+			handles = options.resizable,
+
+			// .ui-resizable has position: relative defined in the stylesheet
+			// but dialogs have to use absolute or fixed positioning
+			position = this.uiDialog.css( "position" ),
+			resizeHandles = typeof handles === "string" ?
+				handles :
+				"n,e,s,w,se,sw,ne,nw";
+
+		function filteredUi( ui ) {
+			return {
+				originalPosition: ui.originalPosition,
+				originalSize: ui.originalSize,
+				position: ui.position,
+				size: ui.size
+			};
+		}
+
+		this.uiDialog.resizable( {
+			cancel: ".ui-dialog-content",
+			containment: "document",
+			alsoResize: this.element,
+			maxWidth: options.maxWidth,
+			maxHeight: options.maxHeight,
+			minWidth: options.minWidth,
+			minHeight: this._minHeight(),
+			handles: resizeHandles,
+			start: function( event, ui ) {
+				that._addClass( $( this ), "ui-dialog-resizing" );
+				that._blockFrames();
+				that._trigger( "resizeStart", event, filteredUi( ui ) );
+			},
+			resize: function( event, ui ) {
+				that._trigger( "resize", event, filteredUi( ui ) );
+			},
+			stop: function( event, ui ) {
+				var offset = that.uiDialog.offset(),
+					left = offset.left - that.document.scrollLeft(),
+					top = offset.top - that.document.scrollTop();
+
+				options.height = that.uiDialog.height();
+				options.width = that.uiDialog.width();
+				options.position = {
+					my: "left top",
+					at: "left" + ( left >= 0 ? "+" : "" ) + left + " " +
+						"top" + ( top >= 0 ? "+" : "" ) + top,
+					of: that.window
+				};
+				that._removeClass( $( this ), "ui-dialog-resizing" );
+				that._unblockFrames();
+				that._trigger( "resizeStop", event, filteredUi( ui ) );
+			}
+		} )
+			.css( "position", position );
+	},
+
+	_trackFocus: function() {
+		this._on( this.widget(), {
+			focusin: function( event ) {
+				this._makeFocusTarget();
+				this._focusedElement = $( event.target );
+			}
+		} );
+	},
+
+	_makeFocusTarget: function() {
+		this._untrackInstance();
+		this._trackingInstances().unshift( this );
+	},
+
+	_untrackInstance: function() {
+		var instances = this._trackingInstances(),
+			exists = $.inArray( this, instances );
+		if ( exists !== -1 ) {
+			instances.splice( exists, 1 );
+		}
+	},
+
+	_trackingInstances: function() {
+		var instances = this.document.data( "ui-dialog-instances" );
+		if ( !instances ) {
+			instances = [];
+			this.document.data( "ui-dialog-instances", instances );
+		}
+		return instances;
+	},
+
+	_minHeight: function() {
+		var options = this.options;
+
+		return options.height === "auto" ?
+			options.minHeight :
+			Math.min( options.minHeight, options.height );
+	},
+
+	_position: function() {
+
+		// Need to show the dialog to get the actual offset in the position plugin
+		var isVisible = this.uiDialog.is( ":visible" );
+		if ( !isVisible ) {
+			this.uiDialog.show();
+		}
+		this.uiDialog.position( this.options.position );
+		if ( !isVisible ) {
+			this.uiDialog.hide();
+		}
+	},
+
+	_setOptions: function( options ) {
+		var that = this,
+			resize = false,
+			resizableOptions = {};
+
+		$.each( options, function( key, value ) {
+			that._setOption( key, value );
+
+			if ( key in that.sizeRelatedOptions ) {
+				resize = true;
+			}
+			if ( key in that.resizableRelatedOptions ) {
+				resizableOptions[ key ] = value;
+			}
+		} );
+
+		if ( resize ) {
+			this._size();
+			this._position();
+		}
+		if ( this.uiDialog.is( ":data(ui-resizable)" ) ) {
+			this.uiDialog.resizable( "option", resizableOptions );
+		}
+	},
+
+	_setOption: function( key, value ) {
+		var isDraggable, isResizable,
+			uiDialog = this.uiDialog;
+
+		if ( key === "disabled" ) {
+			return;
+		}
+
+		this._super( key, value );
+
+		if ( key === "appendTo" ) {
+			this.uiDialog.appendTo( this._appendTo() );
+		}
+
+		if ( key === "buttons" ) {
+			this._createButtons();
+		}
+
+		if ( key === "closeText" ) {
+			this.uiDialogTitlebarClose.button( {
+
+				// Ensure that we always pass a string
+				label: $( "<a>" ).text( "" + this.options.closeText ).html()
+			} );
+		}
+
+		if ( key === "draggable" ) {
+			isDraggable = uiDialog.is( ":data(ui-draggable)" );
+			if ( isDraggable && !value ) {
+				uiDialog.draggable( "destroy" );
+			}
+
+			if ( !isDraggable && value ) {
+				this._makeDraggable();
+			}
+		}
+
+		if ( key === "position" ) {
+			this._position();
+		}
+
+		if ( key === "resizable" ) {
+
+			// currently resizable, becoming non-resizable
+			isResizable = uiDialog.is( ":data(ui-resizable)" );
+			if ( isResizable && !value ) {
+				uiDialog.resizable( "destroy" );
+			}
+
+			// Currently resizable, changing handles
+			if ( isResizable && typeof value === "string" ) {
+				uiDialog.resizable( "option", "handles", value );
+			}
+
+			// Currently non-resizable, becoming resizable
+			if ( !isResizable && value !== false ) {
+				this._makeResizable();
+			}
+		}
+
+		if ( key === "title" ) {
+			this._title( this.uiDialogTitlebar.find( ".ui-dialog-title" ) );
+		}
+	},
+
+	_size: function() {
+
+		// If the user has resized the dialog, the .ui-dialog and .ui-dialog-content
+		// divs will both have width and height set, so we need to reset them
+		var nonContentHeight, minContentHeight, maxContentHeight,
+			options = this.options;
+
+		// Reset content sizing
+		this.element.show().css( {
+			width: "auto",
+			minHeight: 0,
+			maxHeight: "none",
+			height: 0
+		} );
+
+		if ( options.minWidth > options.width ) {
+			options.width = options.minWidth;
+		}
+
+		// Reset wrapper sizing
+		// determine the height of all the non-content elements
+		nonContentHeight = this.uiDialog.css( {
+			height: "auto",
+			width: options.width
+		} )
+			.outerHeight();
+		minContentHeight = Math.max( 0, options.minHeight - nonContentHeight );
+		maxContentHeight = typeof options.maxHeight === "number" ?
+			Math.max( 0, options.maxHeight - nonContentHeight ) :
+			"none";
+
+		if ( options.height === "auto" ) {
+			this.element.css( {
+				minHeight: minContentHeight,
+				maxHeight: maxContentHeight,
+				height: "auto"
+			} );
+		} else {
+			this.element.height( Math.max( 0, options.height - nonContentHeight ) );
+		}
+
+		if ( this.uiDialog.is( ":data(ui-resizable)" ) ) {
+			this.uiDialog.resizable( "option", "minHeight", this._minHeight() );
+		}
+	},
+
+	_blockFrames: function() {
+		this.iframeBlocks = this.document.find( "iframe" ).map( function() {
+			var iframe = $( this );
+
+			return $( "<div>" )
+				.css( {
+					position: "absolute",
+					width: iframe.outerWidth(),
+					height: iframe.outerHeight()
+				} )
+				.appendTo( iframe.parent() )
+				.offset( iframe.offset() )[ 0 ];
+		} );
+	},
+
+	_unblockFrames: function() {
+		if ( this.iframeBlocks ) {
+			this.iframeBlocks.remove();
+			delete this.iframeBlocks;
+		}
+	},
+
+	_allowInteraction: function( event ) {
+		if ( $( event.target ).closest( ".ui-dialog" ).length ) {
+			return true;
+		}
+
+		// TODO: Remove hack when datepicker implements
+		// the .ui-front logic (#8989)
+		return !!$( event.target ).closest( ".ui-datepicker" ).length;
+	},
+
+	_createOverlay: function() {
+		if ( !this.options.modal ) {
+			return;
+		}
+
+		// We use a delay in case the overlay is created from an
+		// event that we're going to be cancelling (#2804)
+		var isOpening = true;
+		this._delay( function() {
+			isOpening = false;
+		} );
+
+		if ( !this.document.data( "ui-dialog-overlays" ) ) {
+
+			// Prevent use of anchors and inputs
+			// Using _on() for an event handler shared across many instances is
+			// safe because the dialogs stack and must be closed in reverse order
+			this._on( this.document, {
+				focusin: function( event ) {
+					if ( isOpening ) {
+						return;
+					}
+
+					if ( !this._allowInteraction( event ) ) {
+						event.preventDefault();
+						this._trackingInstances()[ 0 ]._focusTabbable();
+					}
+				}
+			} );
+		}
+
+		this.overlay = $( "<div>" )
+			.appendTo( this._appendTo() );
+
+		this._addClass( this.overlay, null, "ui-widget-overlay ui-front" );
+		this._on( this.overlay, {
+			mousedown: "_keepFocus"
+		} );
+		this.document.data( "ui-dialog-overlays",
+			( this.document.data( "ui-dialog-overlays" ) || 0 ) + 1 );
+	},
+
+	_destroyOverlay: function() {
+		if ( !this.options.modal ) {
+			return;
+		}
+
+		if ( this.overlay ) {
+			var overlays = this.document.data( "ui-dialog-overlays" ) - 1;
+
+			if ( !overlays ) {
+				this._off( this.document, "focusin" );
+				this.document.removeData( "ui-dialog-overlays" );
+			} else {
+				this.document.data( "ui-dialog-overlays", overlays );
+			}
+
+			this.overlay.remove();
+			this.overlay = null;
+		}
+	}
+} );
+
+// DEPRECATED
+// TODO: switch return back to widget declaration at top of file when this is removed
+if ( $.uiBackCompat !== false ) {
+
+	// Backcompat for dialogClass option
+	$.widget( "ui.dialog", $.ui.dialog, {
+		options: {
+			dialogClass: ""
+		},
+		_createWrapper: function() {
+			this._super();
+			this.uiDialog.addClass( this.options.dialogClass );
+		},
+		_setOption: function( key, value ) {
+			if ( key === "dialogClass" ) {
+				this.uiDialog
+					.removeClass( this.options.dialogClass )
+					.addClass( value );
+			}
+			this._superApply( arguments );
+		}
+	} );
+}
+
+return $.ui.dialog;
+
+} ) );