Merge branch '4.2' into 4.3

* 4.2:
  [Bridge/PhpUnit] fix running composer to install phpunit

Author: nicolas-grekas

bin/simple-phpunit.php

@@ -128,7 +128,7 @@
     $prevRoot = getenv('COMPOSER_ROOT_VERSION');
     putenv("COMPOSER_ROOT_VERSION=$PHPUNIT_VERSION.99");
     // --no-suggest is not in the list to keep compat with composer 1.0, which is shipped with Ubuntu 16.04LTS
-    $exit = proc_close(proc_open("$COMPOSER install --no-dev --prefer-dist --no-progress --ansi", array(), $p));
+    $exit = proc_close(proc_open("$COMPOSER install --no-dev --prefer-dist --no-progress --ansi", array(), $p, getcwd()));
     putenv('COMPOSER_ROOT_VERSION'.(false !== $prevRoot ? '='.$prevRoot : ''));
     if ($exit) {
         exit($exit);