Merge branch '4.4' into 5.1

* 4.4:
  Change test

Author: fabpot

Tests/File/UploadedFileTest.php

@@ -87,11 +87,11 @@ public function testGuessClientExtensionWithIncorrectMimeType()
         $file = new UploadedFile(
             __DIR__.'/Fixtures/test.gif',
             'original.gif',
-            'image/jpeg',
+            'image/png',
             null
         );
 
-        $this->assertEquals('jpeg', $file->guessClientExtension());
+        $this->assertEquals('png', $file->guessClientExtension());
     }
 
     public function testCaseSensitiveMimeType()