Fix targetsetuppage's shadowbuild dirs

* Fix displayed shadow build location
 * Fix shadow build location used by newly set up shadow builds

Task-number: QTCREATORBUG-1599
Reviewed-by: dt

src/plugins/projectexplorer/project.cpp

@@ -229,10 +229,16 @@ QVariantMap Project::toMap() const
 
 QString Project::projectDirectory() const
 {
-    QFileInfo info(file()->fileName());
+    return projectDirectory(file()->fileName());
+}
+
+QString Project::projectDirectory(const QString &proFile)
+{
+    QFileInfo info(proFile);
     return info.absoluteDir().path();
 }
 
+
 bool Project::fromMap(const QVariantMap &map)
 {
     if (map.contains(QLatin1String(EDITOR_SETTINGS_KEY))) {