Description of problem:
Cancelling an operation copying local files to a remote SFTP share in Nautilus results in the share itself being unmounted, presumably as the underlying gvfs service has crashed.

Subsequent attempts to re-establish a mount of the share in network:/// fail, resulting in a dialogue box stating 'Could not display "sftp://<hostname>:22/". The file is of an unknown type'. (This goes away after restarting Nautilus.)

Version-Release number of selected component (if applicable):
nautilus-3.0.2-1.fc15.x86_64
gvfs-1.8.2-1.fc15.x86_64
fuse-2.8.6-1.fc15.x86_64
openssh-5.6p1-34.fc15.1.x86_64

How reproducible:
Always.

Steps to Reproduce:
1. Mount remote SFTP share through Browse Network.
2. Copy stuff to share.
3. Press cancel button in File Operation dialogue part-way through.
  
Actual results:
Share unmounted.

Expected results:
Copy operation stops, share remains.

Additional info:
Output from Nautilus:


$ nautilus
Initializing nautilus-image-converter extension
Initializing nautilus-open-terminal extension
Initializing nautilus-search-tool extension
Initializing nautilus-gdu extension
Shutting down nautilus-gdu extension
Shutting down nautilus-search-tool extension
Shutting down nautilus-open-terminal extension
Shutting down nautilus-image-converter extension

--- Hash table keys for warning below:
--> james
--> James Ettle
--> inode/directory
--> l2051
--> sftp:host=gyro.local
--> 1000
--> network:

(nautilus:23926): Eel-WARNING **: "unique eel_ref_str" hash table still has 7 elements at quit time (keys above)

--- Hash table keys for warning below:
--> network:///
--> sftp://gyro.local/
--> file:///home
--> file:///home/james
--> sftp://gyro.local/mnt/JHE-01-EXT4/home

(nautilus:23926): Eel-WARNING **: "nautilus-directory.c: directories" hash table still has 5 elements at quit time (keys above)