MAGETWO-62464: Travis CI: GD2 imagettfbbox creates image with invalid size

Author: slavvka

lib/internal/Magento/Framework/Image/Adapter/Gd2.php

@@ -748,7 +748,7 @@ protected function _createImageFromTtfText($text, $font)
             $this->_fontSize,
             0,
             0,
-            $height - abs($boundingBox[1]),
+            $height,
             $black,
             $font,
             $text