Customize: Ensure `autosaving` message gets sent to preview after initial change when `saved` state is first dirty.

Amends [41667].
Fixes #42475 for trunk.

Built from https://develop.svn.wordpress.org/trunk@42136


git-svn-id: http://core.svn.wordpress.org/trunk@41967 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/js/customize-controls.js

@@ -9191,12 +9191,14 @@
 
 			api.unbind( 'change', startAutosaving ); // Ensure startAutosaving only fires once.
 
-			api.state( 'saved' ).bind( function( isSaved ) {
+			function onChangeSaved( isSaved ) {
 				if ( ! isSaved && ! api.settings.changeset.autosaved ) {
 					api.settings.changeset.autosaved = true; // Once a change is made then autosaving kicks in.
 					api.previewer.send( 'autosaving' );
 				}
-			} );
+			}
+			api.state( 'saved' ).bind( onChangeSaved );
+			onChangeSaved( api.state( 'saved' ).get() );
 
 			/**
 			 * Request changeset update and then re-schedule the next changeset update time.

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.0-alpha-42134';
+$wp_version = '5.0-alpha-42136';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.