`sanitize_post()` is polymorphic, add an `is_array()` check for `$post` before operating on it as an array.

Props morganestes.
Fixes #33118.

Built from https://develop.svn.wordpress.org/trunk@34080


git-svn-id: http://core.svn.wordpress.org/trunk@34048 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/post-functions.php

@@ -1814,7 +1814,7 @@ function sanitize_post( $post, $context = 'display' ) {
 		foreach ( array_keys(get_object_vars($post)) as $field )
 			$post->$field = sanitize_post_field($field, $post->$field, $post->ID, $context);
 		$post->filter = $context;
-	} else {
+	} elseif ( is_array( $post ) ) {
 		// Check if post already filtered for this context.
 		if ( isset($post['filter']) && $context == $post['filter'] )
 			return $post;

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-alpha-34079';
+$wp_version = '4.4-alpha-34080';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.