support indirect SUBDIRS

that is, .file and .subdir "structs".

Change-Id: I6c7ea5971642802a97461d821cb1544fcc986013
Reviewed-by: Daniel Teske <daniel.teske@digia.com>

src/linguist/lupdate/main.cpp

@@ -361,7 +361,12 @@ static void processProject(
         QStringList subProFiles;
         QDir proDir(proPath);
         foreach (const QString &subdir, visitor.values(QLatin1String("SUBDIRS"))) {
-            QString subPro = QDir::cleanPath(proDir.absoluteFilePath(subdir));
+            QString realdir = visitor.value(subdir + QLatin1String(".subdir"));
+            if (realdir.isEmpty())
+                realdir = visitor.value(subdir + QLatin1String(".file"));
+            if (realdir.isEmpty())
+                realdir = subdir;
+            QString subPro = QDir::cleanPath(proDir.absoluteFilePath(realdir));
             QFileInfo subInfo(subPro);
             if (subInfo.isDir())
                 subProFiles << (subPro + QLatin1Char('/')

tests/auto/linguist/lupdate/testdata/good/proparsingsubs/project.pro

 TEMPLATE = subdirs
-SUBDIRS = win mac unix common
+comm.subdir = common
+SUBDIRS = win mac unix comm