Adding support for variadic arguments fro method in generated proxy classes.

Author: Bartosz Kubicki

lib/internal/Magento/Framework/ObjectManager/Code/Generator/Proxy.php

@@ -155,7 +155,8 @@ protected function _getMethodInfo(\ReflectionMethod $method)
         $parameterNames = [];
         $parameters = [];
         foreach ($method->getParameters() as $parameter) {
-            $parameterNames[] = '$' . $parameter->getName();
+            $name = $parameter->isVariadic() ? '... $' . $parameter->getName() : '$' . $parameter->getName();
+            $parameterNames[] = $name;
             $parameters[] = $this->_getMethodParameterInfo($parameter);
         }