anchor.diff:      }
       int count = 0;
       while (notEofOrValue('}', token.next)) {
  -      token = parseMember(token.next);
  +      token = parseClassMember(token);
         ++count;
       }
       token = token.next;
  
positive.code: 
    bool isModifierOrFactory(Token next) =>
        optional('factory', next) || isModifier(next);
  
    /// ```
    /// classMember:
  
negative.code: 
    bool get inPlainSync => asyncState == AsyncModifier.Sync;
  
    /// Parse a compilation unit.
    ///
    /// This method is only invoked from outside the parser. As a result, this
    /// method takes the next token to be consumed rather than the last consumed
    /// token and returns the token after the last consumed token rather than the
    /// last consumed token.
    ///
    /// ```
    /// libraryDefinition:
    ///   scriptTag?
  