Memory leak in QV4::ErrorObject

There is a 'StackTrace stackTrace ' member in QV4::ErrorObject object.
In Qt5.3 it is declared just as a member of QV4::ErrorObject, and it will be destructed in the destructor of QV4::ErrorObject
But now in Qt5.4 it has been put into QV4::ErrorObject::Data structure and this structure is not destructed during the lifetime of an app which will cause leak of the internal data of QVector(since StackTrace is a QVector).
I can confirm this leak using many leak detector, I tried to submit a patch to address this leak but right now I failed to find a way to sovle this issue.