Issue #2033669 by tim.plunkett, larowlan: Image file objects should be classed.

core/core.services.yml

core/includes/common.inc

core/includes/image.inc

core/lib/Drupal/Component/Utility/Image.php

core/lib/Drupal/Core/Image/Image.php

core/lib/Drupal/Core/Image/ImageFactory.php

core/lib/Drupal/Core/Image/ImageInterface.php

core/modules/file/file.module

core/modules/file/lib/Drupal/file/Tests/ValidatorTest.php

core/modules/image/image.admin.inc

core/modules/image/image.field.inc

core/modules/image/image.install

core/modules/image/image.module

.../Drupal/image/Controller/ImageStyleDownloadController.php

core/modules/image/lib/Drupal/image/ImageEffectInterface.php

.../image/lib/Drupal/image/Plugin/Core/Entity/ImageStyle.php

...e/lib/Drupal/image/Plugin/ImageEffect/CropImageEffect.php

...Drupal/image/Plugin/ImageEffect/DesaturateImageEffect.php

...lib/Drupal/image/Plugin/ImageEffect/ResizeImageEffect.php

...lib/Drupal/image/Plugin/ImageEffect/RotateImageEffect.php