code: private void addCommonHandlers(ChannelPipeline pipeline) {
          pipeline.addLast(Constants.DECOMPRESSOR_HANDLER, new HttpContentDecompressor());
          if (httpTraceLogEnabled) {
              pipeline.addLast(Constants.HTTP_TRACE_LOG_HANDLER,
                      new HttpTraceLoggingHandler(Constants.TRACE_LOG_UPSTREAM));
          }
      }
docs: Add common handlers used in both http2 and http.
  
  @param pipeline the client channel pipeline