Core: Move escape selector into its own module

Ref #9647

ui/core.js

@@ -22,6 +22,7 @@
 			"jquery",
 			"./data",
 			"./disable-selection",
+			"./escape-selector",
 			"./focusable",
 			"./version"
 		], factory );
@@ -90,15 +91,7 @@ $.extend( $.ui, {
 		if ( element && element.nodeName.toLowerCase() !== "body" ) {
 			$( element ).trigger( "blur" );
 		}
-	},
+	}
-
-	// Internal use only
-	escapeSelector: ( function() {
-		var selectorEscape = /([!"#$%&'()*+,./:;<=>?@[\]^`{|}~])/g;
-		return function( selector ) {
-			return selector.replace( selectorEscape, "\\$1" );
-		};
-	} )()
 } );
 
 // plugins

ui/escape-selector.js

@@ -0,0 +1,21 @@
+( function( factory ) {
+	if ( typeof define === "function" && define.amd ) {
+
+		// AMD. Register as an anonymous module.
+		define( [ "jquery", "./version" ], factory );
+	} else {
+
+		// Browser globals
+		factory( jQuery );
+	}
+} ( function( $ ) {
+
+// Internal use only
+return $.ui.escapeSelector = ( function() {
+	var selectorEscape = /([!"#$%&'()*+,./:;<=>?@[\]^`{|}~])/g;
+	return function( selector ) {
+		return selector.replace( selectorEscape, "\\$1" );
+	};
+} )();
+
+} ) );

ui/selectmenu.js

@@ -24,6 +24,7 @@
 			"jquery",
 			"./core",
 			"./version",
+			"./escape-selector",
 			"./widget",
 			"./position",
 			"./menu"

ui/tabs.js

@@ -23,6 +23,7 @@
 		define( [
 			"jquery",
 			"./core",
+			"./escape-selector",
 			"./version",
 			"./widget"
 		], factory );