From e-mail:

I have verified that none of these icons are shipped in the current
TDF distribution, nor are they referred to by the Info.plist file
(which is how Mac OS X specifies relationships between file types and
icons, I don't know if this file is distribution.specific), therefore
they are just dead files in the repository.

Change-Id: I1134642ffa651f3972a81fac2ae992835f6479db