XLIFF empty "target" elements are interpreted as missing

Created by: Anonymous

Original issue 219 created by mihn... on 2012-04-17T18:04:27.000Z:

Steps will reproduce the problem:

1. Create an XLIFFFilter
2. Start reading an XLIFF file that has an empty target
3. Check the TEXT_UNIT events
4. tu.getTarget(trgLocale) returns null

Steps will reproduce the problem without coding:

1. Have an xlf that contains a translation-unit with empty source and empty target
2. Validate in checkmate
3. "Missing translation." error

I would expect an empty "target" in file to result in an empty target in the event, not a null one.

Using m16 on Windows.

Attached test file and fix.