Fix two URLRequestJob subclasses that didn't support cancellation

net/url_request/url_request_error_job.h

 // Copyright (c) 2011 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.
 //
 // Invalid URLs go through this URLRequestJob class rather than being
 // passed to the default job handler.
 
 #ifndef NET_URL_REQUEST_URL_REQUEST_ERROR_JOB_H_
 #define NET_URL_REQUEST_URL_REQUEST_ERROR_JOB_H_
 
 #include "base/memory/weak_ptr.h"
 #include "net/base/net_export.h"
 #include "net/url_request/url_request_job.h"
 
 namespace net {
 
 class NET_EXPORT URLRequestErrorJob : public URLRequestJob {
  public:
   URLRequestErrorJob(URLRequest* request,
                      NetworkDelegate* network_delegate,
                      int error);
 
   void Start() override;
+  void Kill() override;
 
  private:
   ~URLRequestErrorJob() override;
 
   void StartAsync();
 
   int error_;
 
   base::WeakPtrFactory<URLRequestErrorJob> weak_factory_;
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_ERROR_JOB_H_