code: protected void doFinish(RequestBuilder rb) {
          rb.setHeader(STRONG_NAME_HEADER, GWT.getPermutationStrongName());
          rb.setHeader(MODULE_BASE_HEADER, GWT.getModuleBaseURL());
      }
docs: Called by {@link #finish()} prior to returning the RequestBuilder to the
  caller.
  <p>
  The default implementation sets the {@value #STRONG_NAME_HEADER} header to
  the value returned by {@link GWT#getPermutationStrongName()}.
  
  @param rb The RequestBuilder that is currently being configured