code: @Override
      public UpdateRoleDescriptionResult updateRoleDescription(UpdateRoleDescriptionRequest request) {
          request = beforeClientExecution(request);
          return executeUpdateRoleDescription(request);
      }
docs: <p>
  Use <a>UpdateRole</a> instead.
  </p>
  <p>
  Modifies only the description of a role. This operation performs the same function as the
  <code>Description</code> parameter in the <code>UpdateRole</code> operation.
  </p>
  
  @param updateRoleDescriptionRequest
  @return Result of the UpdateRoleDescription operation returned by the service.
  @throws NoSuchEntityException
  The request was rejected because it referenced a resource entity that does not exist. The error message
  describes the resource.
  @throws UnmodifiableEntityException
  The request was rejected because only the service that depends on the service-linked role can modify or
  delete the role on your behalf. The error message includes the name of the service that depends on this
  service-linked role. You must request the change through that service.
  @throws ServiceFailureException
  The request processing has failed because of an unknown error, exception or failure.
  @sample AmazonIdentityManagement.UpdateRoleDescription
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/iam-2010-05-08/UpdateRoleDescription" target="_top">AWS API
  Documentation</a>