Steps to reproduce:

1. Edit the article Content Type and add an Image Asset field type.
2. Create a new article with an image added to the new field.
3. Go to the image content object used for the image asset field in the new article.
4. Move the image content to trash.
5. Go to the trash and delete the image completely.
6. Go to the article, edit it and publish it without any change.

Result:
One is presented with Could not find 'Content' with identifier exception.

Expected result:
The article should be published without any problems.