Creates a new mutable IW3cTraceState instance, optionally inheriting from the parent trace state
and optionally using the provided encoded string value as the initial trace state.
Calls to IW3cTraceState.set and IW3cTraceState.del will modify the current instance
which means that any child instance that is using this instance as a parent will also be indirectly
modified unless the child instance has overridden the value associated with the modified key.
Creates a new mutable IW3cTraceState instance, optionally inheriting from the parent trace state and optionally using the provided encoded string value as the initial trace state. Calls to IW3cTraceState.set and IW3cTraceState.del will modify the current instance which means that any child instance that is using this instance as a parent will also be indirectly modified unless the child instance has overridden the value associated with the modified key.