MAGETWO-55447: Portdown MAGETWO-54718 down to M2.1.x branch

- MAGETWO-54718: [GitHub] Exception thrown where no Product Image file found #5184 #5497 #5871

- (cherry picked from commit 1ef843d)

Author: andimov

app/code/Magento/Catalog/Block/Adminhtml/Product/Helper/Form/Gallery/Content.php

@@ -147,12 +147,8 @@ public function getImagesJson()
                     $fileHandler = $mediaDir->stat($this->_mediaConfig->getMediaPath($image['file']));
                     $image['size'] = $fileHandler['size'];
                 } catch (FileSystemException $e) {
-                    $staticDir = $this->_filesystem->getDirectoryRead(DirectoryList::STATIC_VIEW);
-                    $image['url'] = $this->getImageHelper()->getDefaultPlaceholderUrl('thumbnail');
-                    $fileHandler = $staticDir->stat(
-                        $this->getAssetRepo()->createAsset($this->getImageHelper()->getPlaceholder('thumbnail'))->getPath()
-                    );
-                    $image['size'] = $fileHandler['size'];
+                    $image['url'] = $this->getImageHelper()->getDefaultPlaceholderUrl('small_image');
+                    $image['size'] = 0;
                     $this->_logger->warning($e);
                 }
             }