When copying new bundled themes & plugins, bail early if the distro doesn't include the bundled item. This prevents us from creating an empty directory in the destination when the source doesn't exist. See #22856

git-svn-id: http://core.svn.wordpress.org/trunk@23179 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/update-core.php

@@ -701,6 +701,10 @@ function update_core($from, $to) {
 				$directory = ('/' == $file[ strlen($file)-1 ]);
 				list($type, $filename) = explode('/', $file, 2);
 
+				// Check to see if the bundled items exist before attempting to copy them
+				if ( ! $wp_filesystem->exists( $from . $distro . 'wp-content/' . $file ) )
+					continue;
+
 				if ( 'plugins' == $type )
 					$dest = $wp_filesystem->wp_plugins_dir();
 				elseif ( 'themes' == $type )