Issue #3097583 by kiamlaluno: CreateNew::validateArguments()'s exception...

Issue #3097583 by kiamlaluno: CreateNew::validateArguments()'s exception reports to be for the wrong operation

(cherry picked from commit c314cda0)

core/modules/system/src/Plugin/ImageToolkit/Operation/gd/CreateNew.php

@@ -52,7 +52,7 @@ protected function arguments() {
   protected function validateArguments(array $arguments) {
     // Assure extension is supported.
     if (!in_array($arguments['extension'], $this->getToolkit()->getSupportedExtensions())) {
-      throw new \InvalidArgumentException("Invalid extension ('{$arguments['extension']}') specified for the image 'convert' operation");
+      throw new \InvalidArgumentException("Invalid extension ('{$arguments['extension']}') specified for the image 'create_new' operation");
     }
 
     // Assure integers for width and height.