MAGETWO-69452: Remove zend json from form elements #9754

 - fixed static tests

Author: Oleksii Korshenko

lib/internal/Magento/Framework/Data/Test/Unit/Form/Element/EditorTest.php

@@ -210,13 +210,15 @@ public function testGetConfig()
      */
     public function testGetTranslatedString()
     {
+        $callback = function ($params) {
+            return json_encode($params);
+        };
+
         $this->configMock->expects($this->any())->method('getData')->withConsecutive(['enabled'])->willReturn(true);
         $this->serializer->expects($this->any())
             ->method('serialize')
-            ->willReturnCallback(function ($params) {
-                return json_encode($params);
-            }
-        );
+            ->willReturnCallback($callback);
+
         $html = $this->model->getElementHtml();
 
         $this->assertRegExp('/.*"Insert Image...":"Insert Image...".*/i', $html);