MDVA-291: Issues with Authorize.net direct post running in PHP 7.0.3

Author: Yuriy Denyshchenko

lib/internal/Magento/Framework/App/Config/Data.php

@@ -29,7 +29,8 @@ class Data implements DataInterface
      */
     public function __construct(MetadataProcessor $processor, array $data)
     {
-        $this->_data = $processor->process($data);
+        /** Clone the array to work around a kink in php7 that modifies the argument by reference */
+        $this->_data = $processor->process($this->_arrayClone($data));
         $this->_source = $data;
     }
 
@@ -77,4 +78,19 @@ public function setValue($path, $value)
         }
         $currentElement[$lastKey] = $value;
     }
+
+    /**
+     * Copy array by value
+     *
+     * @param array $data
+     * @return array
+     */
+    private function _arrayClone(array $data)
+    {
+        $clone = [];
+        foreach ($data as $key => $value) {
+            $clone[$key]= $value;
+        }
+        return $clone;
+    }
 }