Merge branch '2.7' into 2.8

* 2.7:
  #20411 fix Yaml parsing for very long quoted strings
  [Doctrine Bridge] fix priority for doctrine event listeners
  Use PHP functions as array_map callbacks when possible
  [Validator] revert wrong Phpdoc change
  Use proper line endings

Author: nicolas-grekas

Tests/FinderTest.php

@@ -318,7 +318,7 @@ public function testGetIterator()
 
         $finder = $this->buildFinder();
         $a = iterator_to_array($finder->directories()->in(self::$tmpDir));
-        $a = array_values(array_map(function ($a) { return (string) $a; }, $a));
+        $a = array_values(array_map('strval', $a));
         sort($a);
         $this->assertEquals($expected, $a, 'implements the \IteratorAggregate interface');
     }