code: public void setHeader(Layout headerLayout) {
          if (getCompositionRoot() != null && this.headerLayout != null) {
              getCompositionRoot().removeComponent(this.headerLayout);
          }
          this.headerLayout = headerLayout;
          if (headerLayout != null) {
              headerLayout.addStyleName(ValoTheme.MENU_TITLE);
              if (getCompositionRoot() != null) {
                  if (this.logo != null) {
                      getCompositionRoot().addComponent(headerLayout, 1);
                  } else {
                      getCompositionRoot().addComponentAsFirst(headerLayout);
                  }
              }
          }
      }
docs: Adds a header to the top of the side bar, below the logo. The {@link ValoTheme#MENU_TITLE} style
  will automatically be added to the layout.
  
  @param headerLayout the layout containing the header, or {@code null} to remove.