Fix lookup in PHP units

Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/trans/formats.py

@@ -415,12 +415,12 @@ class PHPUnit(FileUnit):
     def get_source(self):
         if self.template is not None:
             return self.template.getsource()
-        return self.unit.getsource()
+        return self.unit.getid()
 
     def get_target(self):
         if self.unit is None:
             return ''
-        return self.unit.gettarget()
+        return self.unit.getsource()
 
 
 class FileFormat(object):