code: public WsByteBuffer returnCurrentBuffer() {
          WsByteBuffer buff = null;
          if (HeaderStorage.NOTSET != this.parseIndex) {
              buff = this.parseBuffers[this.parseIndex];
              this.parseIndex--;
          }
          return buff;
      }
docs: Method to remove the current parsing buffer from this object's
  ownership so it can be used by others.
  
  @return WsByteBuffer (null if there is no current buffer)