Report print jobs that are aborted by CUPS as errors.

chrome/browser/chromeos/printing/cups_print_job_notification_manager.cc

 // Copyright 2016 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 "chrome/browser/chromeos/printing/cups_print_job_notification_manager.h"
 
 #include "base/memory/ptr_util.h"
 #include "chrome/browser/chromeos/printing/cups_print_job.h"
 #include "chrome/browser/profiles/profile.h"
 
@@ skipping 42 matching lines @@
 void CupsPrintJobNotificationManager::OnPrintJobDone(CupsPrintJob* job) {
   DCHECK(base::ContainsKey(notification_map_, job));
   notification_map_[job]->OnPrintJobStatusUpdated();
 }
 
 void CupsPrintJobNotificationManager::OnPrintJobError(CupsPrintJob* job) {
   DCHECK(base::ContainsKey(notification_map_, job));
   notification_map_[job]->OnPrintJobStatusUpdated();
 }
 
+void CupsPrintJobNotificationManager::OnPrintJobCancelled(CupsPrintJob* job) {
+  auto notification = notification_map_.find(job);

[xdai1, 2017/02/24 19:17:00]

Why not use the same format in the other functions? e.g.:
DCHECK(base::ContainsKey(notification_map_, job));
notification_map_[job]->OnPrintJobStatusUpdated();

[skau, 2017/02/24 23:09:34]

I've changed it.  I had thought notifications were removed from the map after
they're dismissed but it seems like this never happens.

+  if (notification != notification_map_.end()) {
+    notification->second->OnPrintJobStatusUpdated();
+  }
+}
+
 }  // namespace chromeos