Fix unit test error in qndefrecord.

The typenameformat signal was not always emitted due to insufficient logic
associated with first time initialization of QQmlNdefRecord. This error
only happened when the compiler didn't initialize
QNdefRecordPrivate::typeNameFormat to 0.

Change-Id: Ieba0a1d7c940c40980ff455ca5c1665c298c0527
Reviewed-by: Fabian Bumberger <fbumberger@rim.com>
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>