cloneMap<K, V> method
Deep-clones an untyped Map<K, dynamic> with circular reference detection.
Throws CircularReferenceCloneException if a circular reference is detected.
Implementation
@override
Map<K, dynamic> cloneMap<K, V>(Map<K, V> source) {
_assertCircRef(source.hashCode);
_nestIndex++;
final cloned = super.cloneMap<K, V>(source);
_nestIndex--;
return cloned;
}