Customizer: Import missing `wp.customize.Control.prototype._toggleActive`.

Check also if `completeCallback` is set before calling it.

props westonruter.
see #30701.
Built from https://develop.svn.wordpress.org/trunk@30871


git-svn-id: http://core.svn.wordpress.org/trunk@30861 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/js/customize-controls.js

@@ -252,7 +252,9 @@
 			if ( ! $.contains( document, this.container ) ) {
 				// jQuery.fn.slideUp is not hiding an element if it is not in the DOM
 				this.container.toggle( active );
-				args.completeCallback();
+				if ( args.completeCallback ) {
+					args.completeCallback();
+				}
 			} else if ( active ) {
 				this.container.stop( true, true ).slideDown( duration, args.completeCallback );
 			} else {
@@ -820,7 +822,7 @@
 			// Watch for changes to the section state
 			inject = function ( sectionId ) {
 				var parentContainer;
-				if ( ! sectionId ) { // @todo allow a control to be embeded without a section, for instance a control embedded in the frontend
+				if ( ! sectionId ) { // @todo allow a control to be embedded without a section, for instance a control embedded in the frontend
 					return;
 				}
 				// Wait for the section to be registered
@@ -878,7 +880,9 @@
 			if ( ! $.contains( document, this.container ) ) {
 				// jQuery.fn.slideUp is not hiding an element if it is not in the DOM
 				this.container.toggle( active );
-				args.completeCallback();
+				if ( args.completeCallback ) {
+					args.completeCallback();
+				}
 			} else if ( active ) {
 				this.container.slideDown( args.duration, args.completeCallback );
 			} else {
@@ -913,6 +917,13 @@
 		 */
 		deactivate: Container.prototype.deactivate,
 
+		/**
+		 * Re-use _toggleActive from Container class.
+		 *
+		 * @access private
+		 */
+		_toggleActive: Container.prototype._toggleActive,
+
 		dropdownInit: function() {
 			var control      = this,
 				statuses     = this.container.find('.dropdown-status'),