Current instructions for translators say to edit either the po or XLIFF files we ship to them. Our scripts for merging the translations back deliberately ignores the XLIFF files since r27419. We should probably stop share the XLIFF files with translators as well.
Bgu 5661 has changed things so we no longer use XLIFF files in our translation work flow.
Bug 5661*
Searched for XLIFF and din't find anything after latest made changes.