c1518c3fde
Before this commit, it was not possible to set the status code of an HTTP response without throwing an exception if it was already committed. The consequence was a lot of errors in the logs for long lived HTTP exchanges like Server-Sent Events for example. After this commit, ServerHttpResponse#setStatusCode() returns true if the operation succeeded and false if the status code has not been set because the response has already been committed. In term of implementation, that makes status code managed consistently with headers and cookies: AbstractServerHttpResponse#setStatusCode() stores the status code that will be effectively set later in the response lifecycle by the HTTP server via AbstractServerHttpResponse#writeStatusCode() when the response will be committed.