Fix two URLRequestJob subclasses that didn't support cancellation

net/url_request/url_request_error_job.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/url_request/url_request_error_job.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 10 matching lines @@
       weak_factory_(this) {}
 
 URLRequestErrorJob::~URLRequestErrorJob() {}
 
 void URLRequestErrorJob::Start() {
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
       base::Bind(&URLRequestErrorJob::StartAsync, weak_factory_.GetWeakPtr()));
 }
 
+void URLRequestErrorJob::Kill() {
+  weak_factory_.InvalidateWeakPtrs();
+  URLRequestJob::Kill();
+}
+
 void URLRequestErrorJob::StartAsync() {
   NotifyStartError(URLRequestStatus(URLRequestStatus::FAILED, error_));
 }
 
 }  // namespace net