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The TypedData::setValue() method invokes the onChange() method on the parent typed data object.
While the parent is of type TraversableTypedDataInterface, that method is not part of the interface.
This can be fixed now because we've got a proper interface for the parent typed data which is TraversableTypedDataInterface.
Note this is not an issue introduced by that new interface as it was existing before of that. It is an issue that can be fixed now because we've got that new interface.
Move that method one level up in the interface hierarchy, to TraversableTypedDataInterface
User interface changes
None. Method is just moved to parent interface.