`WP_Query` taxonomy query vars should be set to first of multiple taxonomies.

This provides better parity with `get_queried_object()`, which will return the
first taxonomy/term matched by the current query.

[29891] introduced the abnormal behavior for the 'taxonomy' and 'term'
query vars.

Props Chouby.
Fixes #35619.
Built from https://develop.svn.wordpress.org/trunk@36484


git-svn-id: http://core.svn.wordpress.org/trunk@36451 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/query.php

@@ -2857,6 +2857,9 @@ class WP_Query {
 						} else {
 							$q['term_id'] = $queried_items['terms'][0];
 						}
+
+						// Take the first one we find.
+						break;
 					}
 				}
 			}

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.5-alpha-36483';
+$wp_version = '4.5-alpha-36484';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.