anchor.diff:    /// The last token in the type reference.
     Token end;
   
  -  /// The tokens before the start of type variables of function types seen
  -  /// during analysis. Notice that the tokens in this list might precede
  -  /// either `'<'` or `'('` as not all function types have type parameters.
  +  /// The `Function` tokens before the start of type variables of function types
  +  /// as seen during analysis.
     Link<Token> typeVariableStarters = const Link<Token>();
   
     /// If the receiver represents a generalized function type then this indicates
  
positive.code:   return false;
  }
  
  Token skipTypeVariables(Token token) {
    assert(optional('<', token));
    Token endGroup = token.endGroup;
    if (endGroup == null) {
      return null;
    }
  
    // The scanner sets the endGroup in situations like this: C<T && T>U;
    // Scan the type arguments to assert there are no operators.
    // TODO(danrubel): Fix the scanner to do this scanning.
    token = token.next;
    while (token != endGroup) {
      if (token.isKeywordOrIdentifier ||
          optional(',', token) ||
          optional('.', token) ||
          optional('<', token) ||
          optional('>', token) ||
          optional('>>', token) ||
          optional('@', token)) {
        // ok
      } else if (optional('(', token)) {
        token = token.endGroup;
      } else {
        return null;
      }
      token = token.next;
    }
    return endGroup;
  }
  
  /// Instances of [ComplexTypeInfo] are returned by [computeType] to represent
  /// type references that cannot be represented by the constants above.
  class ComplexTypeInfo implements TypeInfo {
  
negative.code:   void computeRest(Token token, bool required) {
      while (optional('Function', token)) {
        Token typeVariableStart = token;
        // TODO(danrubel): Consider caching TypeParamOrArgInfo
        token = computeTypeParamOrArg(token, true).skip(token);
        token = token.next;
        if (!optional('(', token)) {
          break; // Not a function type.
        }
  