Customize: Allow control subclasses to add to the `deferred` object before the base class initializes.

Update the `CodeEditorControl`'s `codemirror` deferred to be set before calling the parent class's `initialize` method. Since the `ready` method may be called directly by `initialize` it may be too late to add a new `Deferred` to the control's `deferred` property after calling the base control class's `initialize`.

Amends [41958].
See #41897.

Built from https://develop.svn.wordpress.org/trunk@41960


git-svn-id: http://core.svn.wordpress.org/trunk@41794 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/js/customize-controls.js

@@ -3419,9 +3419,9 @@
 				control.templateSelector = 'customize-control-' + control.params.type + '-content';
 			}
 
-			control.deferred = {
+			control.deferred = _.extend( control.deferred || {}, {
 				embedded: new $.Deferred()
-			};
+			} );
 			control.section = new api.Value();
 			control.priority = new api.Value();
 			control.active = new api.Value();
@@ -5127,8 +5127,10 @@
 		 */
 		initialize: function( id, options ) {
 			var control = this;
-			api.Control.prototype.initialize.call( this, id, options );
-			control.deferred.codemirror = $.Deferred();
+			control.deferred = _.extend( control.deferred || {}, {
+				codemirror: $.Deferred()
+			} );
+			api.Control.prototype.initialize.call( control, id, options );
 		},
 
 		/**

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9-beta3-41959';
+$wp_version = '4.9-beta3-41960';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.