thumbnailUri 
  An URI to a thumbnail of this file. This is used to show a preview of the file. Supported schemes:
- content 
- file 
- android.resource 
- http 
- https 
If null, a default icon will be shown, depending on the file type.
An URI to a thumbnail of this file. This is used to show a preview of the file. Supported schemes:
content
file
android.resource
http
https
If null, a default icon will be shown, depending on the file type.