* Adds additional overloads/specializations which are required when
passing JS::Handle<T>/JS::MutableHandle<T> types to different functions.
* Replaces GetPropertyJS with a GetProperty specialization.
* Allows us to avoid the implementation of ToJSVal specializations for
JS::Value and JS::HandleValue. Such conversions should only happen if
there's no way around it and if you are aware of it.
* Adds test to make sure that all potentially required specializations
with custom implementations are instantiated. This should help prevent
introducing bugs in temporarily unused code.
Refs #2415
This was SVN commit r15567.