anchor.diff:          });
         }
       }
  -    return imports.values;
  +    return imports!.values;
     }
   
     /// Convert this [KLibraryData] to the corresponding [JLibraryData].
  
positive.code:   @override
    final ir.Member node;
  
    Iterable<ConstantValue> _metadata;
  
    @override
    StaticTypeCache staticTypes;
  
    KMemberDataImpl(this.node);
  
  
negative.code:       setterMap = const <String, ir.Member>{};
      } else {
        setterMap = <String, ir.Member>{};
        _setterMap!.forEach((String name, ir.Member node) {
          MemberEntity member = kElementMap.getMember(node);
          if (liveMemberUsage.containsKey(member)) {
            setterMap[name] = node;
  