Compile fix with namespaces

Change-Id: I4104cf431643d559934f78a42046a3a8f1901e9b
Reviewed-by: hjk <qthjk@ovi.com>

src/plugins/debugger/qml/qmlengine.h

@@ -39,7 +39,9 @@
 
 #include <QtNetwork/QAbstractSocket>
 
+QT_BEGIN_NAMESPACE
 class QTextDocument;
+QT_END_NAMESPACE
 
 namespace Core {
 class IEditor;