Google Code-in

In MediaWiki core's includes/registration/ directory, there are a few (two I think) places we use array_map for very simple operations:

$this->globals["wgExtensionMessagesFiles"] += array_map( function ( $file ) use ( $dir ) {
  return "$dir/$file";
}, $info['ExtensionMessagesFiles'] );

Since these are quick operations, we can make this code faster by using a foreach loop instead of array_map with a closure (unnecessary function calls are expensive).

• https://secure.php.net/manual/en/function.array-map.php
• https://secure.php.net/manual/en/control-structures.foreach.php

You are expected to provide a patch in Wikimedia Gerrit. See https://www.mediawiki.org/wiki/Gerrit/Tutorial for how to set up Git and Gerrit.