anchor.diff:    /// be set to the root class for type parameters without an explicit bound.
     DartType bound;
   
  +  /// If this is a type parameter of a concrete generic method, its formal
  +  /// safety.  Otherwise ignored.
  +  ///
  +  /// See [FormalSafety] for details.
  +  FormalSafety formalSafety = FormalSafety.safe;
  +
  +  /// If this is a type parameter of a generic method, its interface safety.
  +  /// Otherwise ignored.
  +  ///
  +  /// See [InterfaceSafety] for details.
  +  InterfaceSafety interfaceSafety = InterfaceSafety.typed;
  +
     TypeParameter([this.name, this.bound]);
   
     accept(TreeVisitor v) => v.visitTypeParameter(this);
  
positive.code:   Expression receiver;
    Reference targetReference;
    Arguments arguments;
  
    DirectMethodInvocation(
        Expression receiver, Procedure target, Arguments arguments)
  
negative.code:   ///
    /// Should be null in other cases.
    Expression initializer; // May be null.
  
    /// If this is a formal parameter of a concrete method, its formal safety.
    /// Otherwise ignored.
    ///
    /// See [FormalSafety] for details.
    FormalSafety formalSafety = FormalSafety.safe;
  
    /// If this is a formal parameter of a method, its interface safety.
    /// Otherwise ignored.
    ///
    /// See [InterfaceSafety] for details.
    InterfaceSafety interfaceSafety = InterfaceSafety.typed;
  
    VariableDeclaration(this.name,
        {this.initializer,
  