MAGETWO-60355: [Backport] - Production mode cannot be enabled - for 2.1

Author: Bohdan Korablov

lib/internal/Magento/Framework/ObjectManager/Config/Compiled.php

@@ -129,15 +129,9 @@ public function getPreference($type)
      */
     public function extend(array $configuration)
     {
-        $this->arguments = isset($configuration['arguments'])
-            ? array_replace($this->arguments, $configuration['arguments'])
-            : $this->arguments;
-        $this->virtualTypes = isset($configuration['instanceTypes'])
-            ? array_replace($this->virtualTypes, $configuration['instanceTypes'])
-            : $this->virtualTypes;
-        $this->preferences = isset($configuration['preferences'])
-            ? array_replace($this->preferences, $configuration['preferences'])
-            : $this->preferences;
+        $this->arguments = $configuration['arguments'];
+        $this->virtualTypes = $configuration['instanceTypes'];
+        $this->preferences = $configuration['preferences'];
     }
 
     /**