Instead throw an IllegalStateException which is also resulting in an internal server error. Logging a warning is not needed since internal server errors are anyway logged. Throwing a RestApiException to signal internal server errors is bad since all RestApiExceptions are exempt from retries and auto-tracing. Signed-off-by: Edwin Kempin <ekempin@google.com> Change-Id: I5d90a64d5fc65905034c3ef85e0e674b4c7d28c2