anchor.diff:        Iterable<String> createAnnotations,
         Iterable<String> returnsAnnotations,
         TypeLookup lookupType,
  -      {bool isJsInterop}) {
  +      {required bool isJsInterop}) {
       _behavior = NativeBehavior();
       DartType returnType = type.returnType;
       // Note: For dart:html and other internal libraries we maintain, we can
  
positive.code:         nullType: commonElements.nullType);
  
      if (!sideEffectsAreEncodedInSpecString) {
        SideEffectsVisitor(behavior.sideEffects).visit(behavior.codeTemplate.ast);
      }
      if (!throwBehaviorFromSpecString) {
        behavior.throwBehavior =
            ThrowBehaviorVisitor().analyze(behavior.codeTemplate.ast);
      }
  
      return behavior;
  
negative.code:       TypeLookup lookupType,
        DiagnosticReporter reporter,
        CommonElements commonElements,
        {List<String>? validTags}) {
      void setSideEffects(SideEffects newEffects) {
        behavior.sideEffects.setTo(newEffects);
      }
  