How to permanently turn off online results

I don't like getting online results when searching in my dashboard, so I went to System Settings > Security & Privacy > Search, and I turned the setting off:

But when I restart my machine, the setting is always reset to:

So how can I permanently disable it without it turning on again after a restart?

Information Update:

I have had a look at the post that this has been marked as a possible duplicate of, and I don't think that my question really is a duplicate of it, as the other question is asking about how to set it globally, and I am not, I am only wanting to set it for one user, so the fact that it is not global is not the problem, the problem is that it is not sticking for that one user, and just resetting to its default state after a restart. In fact, I don't want it to be set globally, and the answers from the other question only really explain how to do that.

OS Information:

Description:    Ubuntu 15.04
Release:    15.04

Package Information:

unity:
  Installed: 7.3.2+15.04.20150420-0ubuntu1
  Candidate: 7.3.2+15.04.20150420-0ubuntu1
  Version table:
 *** 7.3.2+15.04.20150420-0ubuntu1 0
        500 http://gb.archive.ubuntu.com/ubuntu/ vivid/main amd64 Packages
        100 /var/lib/dpkg/status

You can switch off online search results with the command:

gsettings set com.canonical.Unity.Lenses remote-content-search 'none'

To make the command run on startup, and make sure it is set after a restart, add the following to your startup applications:

gsettings set com.canonical.Unity.Lenses remote-content-search 'none'