Index: wp-admin/includes/plugin.php
===================================================================
--- wp-admin/includes/plugin.php	(revision 43583)
+++ wp-admin/includes/plugin.php	(working copy)
@@ -281,10 +281,8 @@
 					}
 					closedir( $plugins_subdir );
 				}
-			} else {
-				if ( substr( $file, -4 ) == '.php' ) {
-					$plugin_files[] = $file;
-				}
+			} elseif ( substr( $file, -4 ) == '.php' ) {
+				$plugin_files[] = $file;
 			}
 		}
 		closedir( $plugins_dir );