Please describe the problem:
When performing a drag and drop from a source folder to a target folder that are both in the same local file system Nautilus tries to move the source file. This is true even if the source file is in the folder of another user and that we only have read access to both the source folder and the source file.


Steps to reproduce:
1. Create two different user accounts for example 'clark' and 'kent'.
2. Have the user 'clark' create a local folder named 'source' and a file named 'source-file.txt' inside that very same folder. 
3. Give the ownership of the folder and the file to the user 'clark': chown -R clark source/
4. Give the right permissions in order to let the user 'kent' read the file 'source-file.txt': chmod -R a+rX 'source/'
5. Have the user 'kent' create a folder named 'target' and make sure that the folder is a local folder, preferably in the same file system as the folder 'source'
5. Have the user 'kent' browse both folders with nautilus.
6. Have the user 'kent' initialize a drag motion of the file 'source-file.txt' into the folder 'target'.


Actual results:
Nautilus will fail to perform the operation. A dialog shows up:
Title: Error while moving.
Content: "source-file.txt" cannot be moved because you do not have permissions to change it or its parent folder.

Expected results:
I would expect the file to be copied and not moved.

Does this happen every time?


Other information: