"New Class" wizard: Check custom base class for QObject parent

That is, if the user specifies a custom base class, we check whether its
constructor takes a "QObject *parent" parameter, and if it does, we give
the derived class one as well.
This is technically a heuristic, but the pattern is pretty stable in the
Qt world.

Fixes: QTCREATORBUG-25156
Change-Id: Ie64440929df61cca7258d6d692c5de62970f9a65
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/cpptools/cppmodelmanager.h

@@ -98,6 +98,8 @@ public:
 
     static CppModelManager *instance();
 
+    void registerJsExtension();
+
      // Documented in source file.
      enum ProgressNotificationMode {
         ForcedProgressNotification,