Merge branch '4.2'

* 4.2: (26 commits)
  Apply php-cs-fixer rule for array_key_exists()
  [Cache] fix warming up cache.system and apcu
  [Security] Change FormAuthenticator if condition
  handles multi-byte characters in autocomplete
  speed up tests running them without debug flag
  [Translations] added missing Croatian validators
  Fix getItems() performance issue with RedisCluster (php-redis)
  [VarDumper] Keep a ref to objects to ensure their handle cannot be reused while cloning
  IntegerType: reject submitted non-integer numbers
  be keen to newcomers
  [HttpKernel] Fix possible infinite loop of exceptions
  fixed CS
  [Validator] Added missing translations for Afrikaans
  do not validate non-submitted form fields in PATCH requests
  Update usage example in ArrayInput doc block.
  [Console] Prevent ArgvInput::getFirstArgument() from returning an option value
  [Validator] Fixed duplicate UUID
  fixed CS
  [EventDispatcher] Fix unknown priority
  Avoid mutating the Finder when building the iterator
  ...

Author: nicolas-grekas

Crawler.php

@@ -985,7 +985,7 @@ private function relativize(string $xpath): string
         $expressions = [];
 
         // An expression which will never match to replace expressions which cannot match in the crawler
-        // We cannot simply drop
+        // We cannot drop
         $nonMatchingExpression = 'a[name() = "b"]';
 
         $xpathLen = \strlen($xpath);

Field/FileFormField.php

@@ -60,7 +60,7 @@ public function setValue($value)
 
             // copy to a tmp location
             $tmp = sys_get_temp_dir().'/'.strtr(substr(base64_encode(hash('sha256', uniqid(mt_rand(), true), true)), 0, 7), '/', '_');
-            if (array_key_exists('extension', $info)) {
+            if (\array_key_exists('extension', $info)) {
                 $tmp .= '.'.$info['extension'];
             }
             if (is_file($tmp)) {

FormFieldRegistry.php

@@ -57,7 +57,7 @@ public function remove($name)
         $target = &$this->fields;
         while (\count($segments) > 1) {
             $path = array_shift($segments);
-            if (!array_key_exists($path, $target)) {
+            if (!\array_key_exists($path, $target)) {
                 return;
             }
             $target = &$target[$path];
@@ -80,7 +80,7 @@ public function &get($name)
         $target = &$this->fields;
         while ($segments) {
             $path = array_shift($segments);
-            if (!array_key_exists($path, $target)) {
+            if (!\array_key_exists($path, $target)) {
                 throw new \InvalidArgumentException(sprintf('Unreachable field "%s"', $path));
             }
             $target = &$target[$path];