[BUGFIX] Check if 'name' parameter is set before reading it

Example when it doesn't need to be set is PATCH method

src/SGalinski/TypoScriptBackendBundle/Controller/AbstractPropertyController.php

@@ -216,8 +216,8 @@ abstract class AbstractPropertyController extends FOSRestController {
 	private function processForm(Property $property, array $parameters, $method = 'PUT') {
 		$form = $this->createForm(new PropertyType(), $property, ['method' => $method]);
 
-		if (!isset($parameters['urlName'])) {
-			// If urlName is not already calculated and set in request parameters, then set it now.
+		if (!isset($parameters['urlName']) && isset($parameters['name'])) {
+			// If urlName is not already calculated and set in request parameters and if name parameter is set, then set urlName.
 			$property->setName($parameters['name']);
 			$parameters['urlName'] = $property->getUrlName();
 		}

src/SGalinski/TypoScriptBackendBundle/Controller/AbstractTypeController.php

@@ -220,8 +220,8 @@ abstract class AbstractTypeController extends FOSRestController {
 	private function processForm(Type $type, array $parameters, $method = 'PUT') {
 		$form = $this->createForm(new TypeType(), $type, ['method' => $method]);
 
-		if (!isset($parameters['urlName'])) {
-			// If urlName is not already calculated and set in request parameters, then set it now.
+		if (!isset($parameters['urlName']) && isset($parameters['name'])) {
+			// If urlName is not already calculated and set in request parameters and if name parameter is set, then set urlName.
 			$type->setName($parameters['name']);
 			$parameters['urlName'] = $type->getUrlName();
 		}