A folder can contain 2 images with the same name

Description

Step to reproduce

1. Make sure an active project is selected on project mode bar (to ensure that: uploaded content is in draft status).
2. Select the folder 'For All Sites'.
3. Upload an image with name rose.jpg. Don't publish the image.
4. Create Folder A > upload the image rose.jpg to folder A.
5. Move Folder A to trash.
6. Open the trash.
7. Select the image rose.jpg under Folder A.
8. Restore it to folder 'For All Sites'.

Expected:
Message appears "The Image "rose.jpg" already exists", and you can't restore the image to the folder.

Actual:
The restore is successful, so there are 2 images with the name "rose.jpg" in the folder 'For All Sites'.