Taxonomy: When querying terms, ensure `$taxonomies` is an array.

This avoids PHP notices that otherwise arise when no `taxonomy`
parameter is passed to `get_terms()` or `WP_Term_Query`.

Props dlh.
Fixes #39932.
Built from https://develop.svn.wordpress.org/trunk@40147


git-svn-id: http://core.svn.wordpress.org/trunk@40086 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-term-query.php

@@ -323,7 +323,7 @@ class WP_Term_Query {
 		 */
 		do_action( 'pre_get_terms', $this );
 
-		$taxonomies = $args['taxonomy'];
+		$taxonomies = (array) $args['taxonomy'];
 
 		// Save queries by not crawling the tree in the case of multiple taxes or a flat tax.
 		$has_hierarchical_tax = false;

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-40146';
+$wp_version = '4.8-alpha-40147';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.