This fixes bug #1182766 ("Edit QR code" and "Change the QR colors" icons missing) by adding a custom search path to the default icon theme, and distributing the icons in question within our codebase.
The local path is "data/media/" and the icons are: -preferences-color-symolic -text-editor-symbolic -printer-symbolc
The last icon was added to fix a scaling error in 12.04, and was renamed to -qreator-printer-symbolic