Display user full name in locked notification instead of 'userid'

1. install nuxeo 7.10
2. install Drive 2.4.5
3. Login as User1 in "Safari"
4. Login as User2 in "Chrome" browser.
5. User1 shares a folder with a file with 'Manage Everything' to User2.
6. DRIVE, connect as User2 and wait for sync completion.
7. As "User1", Lock the file
8. As "User2", DO NOT REFRESH the page and click on direct edit icon.

Actual Result:
Locked notification is displayed with 'userid'

The behavior is different on Windows and thus could not be double-checked (see NXDRIVE-892)