anchor.diff:          implementsClause?.interfaces,
           CompileTimeErrorCode.IMPLEMENTS_REPEATED,
         );
  -      if (!disableConflictingGenericsCheck) {
  -        _checkForConflictingGenerics(node);
  -      }
  +      _checkForConflictingGenerics(node);
       }
     }
   
  
positive.code:    * Initialize a newly created error verifier.
     */
    ErrorVerifier(ErrorReporter errorReporter, this._currentLibrary,
        this._typeProvider, this._inheritanceManager, bool enableSuperMixins,
        {this.disableConflictingGenericsCheck = false})
        : _errorReporter = errorReporter,
          _uninstantiatedBoundChecker =
              _UninstantiatedBoundChecker(errorReporter),
  
negative.code: 
    final _UninstantiatedBoundChecker _uninstantiatedBoundChecker;
  
    /// The features enabled in the unit currently being checked for errors.
    FeatureSet _featureSet;
  
  