Ticket #7875: 7875.8.diff

Index: wp-admin/includes/class-wp-upgrader.php
===================================================================
--- wp-admin/includes/class-wp-upgrader.php     (revision 11076)
+++ wp-admin/includes/class-wp-upgrader.php     (working copy)
@@ -722,8 +722,12 @@
                if ( is_string($errors) ) {
                        $this->feedback($errors);
                } elseif ( is_wp_error($errors) && $errors->get_error_code() ) {
-                       foreach ( $errors->get_error_messages() as $message )
-                               $this->feedback($message);
+                       foreach ( $errors->get_error_messages() as $message ) {
+                               if ( $errors->get_error_data() )
+                                       $this->feedback($message . ' ' . $errors->get_error_data() );
+                               else
+                                       $this->feedback($message);
+                       }
                }
        }
 
@@ -731,10 +735,12 @@
                if ( isset( $this->upgrader->strings[$string]) )
                        $string = $this->upgrader->strings[$string];
 
-               $args = func_get_args();
-               $args = array_splice($args, 1);
-               if ( !empty($args) )
-                       $string = vsprintf($string, $args);
+               if ( strpos($string, '%') !== false ) {
+                       $args = func_get_args();
+                       $args = array_splice($args, 1);
+                       if ( !empty($args) )
+                               $string = vsprintf($string, $args);
+               }
                if ( empty($string) )
                        return;
                show_message($string);