Docs: Fix typo in references to WP_Error in some DocBlocks.

See #51800.
Built from https://develop.svn.wordpress.org/trunk@49769


git-svn-id: http://core.svn.wordpress.org/trunk@49492 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/taxonomy.php

@@ -724,10 +724,10 @@ function unregister_taxonomy_for_object_type( $taxonomy, $object_type ) {
 /**
  * Retrieve object_ids of valid taxonomy and term.
  *
- * The strings of $taxonomies must exist before this function will continue. On
- * failure of finding a valid taxonomy, it will return an WP_Error class, kind
- * of like Exceptions in PHP 5, except you can't catch them. Even so, you can
- * still test for the WP_Error class and get the error message.
+ * The strings of $taxonomies must exist before this function will continue.
+ * On failure of finding a valid taxonomy, it will return a WP_Error class,
+ * kind of like Exceptions in PHP 5, except you can't catch them. Even so,
+ * you can still test for the WP_Error class and get the error message.
  *
  * The $terms aren't checked the same as $taxonomies, but still need to exist
  * for $object_ids to be returned.