Clicking nautilus icon in the unity launcher does not bring existing nautilus window to focus

[James Hiew]

Ubuntu version:
Output of `lsb_release -rd`
Description: Ubuntu 14.04.1 LTS
Release: 14.04

Package versions:
Output of `apt-cache policy nautilus`
nautilus:
  Installed: 1:3.10.1-0ubuntu9.3
  Candidate: 1:3.10.1-0ubuntu9.3
  Version table:
 *** 1:3.10.1-0ubuntu9.3 0
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     1:3.10.1-0ubuntu8 0
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages

Output of `apt-cache policy unity`
unity:
  Installed: 7.2.2+14.04.20140714-0ubuntu1.1
  Candidate: 7.2.2+14.04.20140714-0ubuntu1.1
  Version table:
 *** 7.2.2+14.04.20140714-0ubuntu1.1 0
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu/ trusty-security/main amd64 Packages
        100 /var/lib/dpkg/status
     7.2.0+14.04.20140416-0ubuntu1 0
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages

Context:
Had exactly one nautilus window in existence, but minimised to the launcher. This existing nautilus window was pointed to the directory of an external device (i.e. /media/james/HDD1)

Expected behaviour:
Clicking the nautilus icon in the unity launcher should unminimise this existing nautilus window.

Actual behaviour:
Clicking on the nautilus icon in the unity launcher caused a new nautilus window to open. The existing nautilus window is still able to be unminimised by either Alt-Tabbing to it or by clicking the external device icon in the unity launcher.