anchor.diff:      FReader : TLookaheadReader;
   
       // Push/pop a new JSON context onto/from the stack.
  +    procedure ResetContextStack;
       procedure PushContext( aCtx : TJSONBaseContext);
       procedure PopContext;
   
  
positive.code: 
  procedure TJSONProtocolImpl.WriteMessageBegin( aMsg : IMessage);
  begin
    WriteJSONArrayStart;
    WriteJSONInteger(VERSION);
  
  
negative.code: 
  function TJSONProtocolImpl.ReadMessageBegin: IMessage;
  begin
    ResetContextStack;  // THRIFT-1473
  
    result := TMessageImpl.Create;
    ReadJSONArrayStart;
  
  