Add missing event attribute

serializers/akonadi_serializer_kalarm.cpp

 /*
  *  akonadi_serializer_kalarm.cpp  -  Akonadi resource serializer for KAlarm
- *  SPDX-FileCopyrightText: 2009-2019 David Jarvie <djarvie@kde.org>
+ *  SPDX-FileCopyrightText: 2009-2020 David Jarvie <djarvie@kde.org>
  *
  *  SPDX-License-Identifier: LGPL-2.0-or-later
  */
@@ -264,6 +264,9 @@ void SerializerPluginKAlarm::compare(AbstractDifferencesReporter *reporter, cons
     if (eventL.commandXterm() != eventR.commandXterm()) {
         reportDifference(reporter, KAEventFormatter::CommandXTerm);
     }
+    if (eventL.commandHideError() != eventR.commandHideError()) {
+        reportDifference(reporter, KAEventFormatter::CommandHideError);
+    }
     if (eventL.emailSubject() != eventR.emailSubject()) {
         reportDifference(reporter, KAEventFormatter::EmailSubject);
     }

serializers/kaeventformatter.cpp

 /*
  *  kaeventformatter.cpp  -  converts KAlarmCal::KAEvent properties to text
- *  SPDX-FileCopyrightText: 2010-2019 David Jarvie <djarvie@kde.org>
+ *  SPDX-FileCopyrightText: 2010-2020 David Jarvie <djarvie@kde.org>
  *
  *  SPDX-License-Identifier: LGPL-2.0-or-later
  */
@@ -133,6 +133,8 @@ QString KAEventFormatter::label(Parameter param)
         return i18nc("@label", "Log file");
     case CommandXTerm:
         return i18nc("@label Execute in terminal window", "Execute in terminal");
+    case CommandHideError:
+        return i18nc("@label", "Hide command error");
 
     case EmailSubject:
         return i18nc("@label", "Email subject");
@@ -220,6 +222,7 @@ bool KAEventFormatter::isApplicable(Parameter param) const
     case Command:
     case LogFile:
     case CommandXTerm:
+    case CommandHideError:
         return mEvent.actionSubType() == KAEvent::COMMAND;
 
     case EmailSubject:
@@ -385,6 +388,8 @@ QString KAEventFormatter::value(Parameter param) const
         return mEvent.logFile();
     case CommandXTerm:
         return trueFalse(mEvent.commandXterm());
+    case CommandHideError:
+        return trueFalse(mEvent.commandHideError());
 
     case EmailSubject:
         return mEvent.emailSubject();

serializers/kaeventformatter.h

 /*
  *  kaeventformatter.h  -  converts KAlarmCal::KAEvent properties to text
- *  SPDX-FileCopyrightText: 2010-2019 David Jarvie <djarvie@kde.org>
+ *  SPDX-FileCopyrightText: 2010-2020 David Jarvie <djarvie@kde.org>
  *
  *  SPDX-License-Identifier: LGPL-2.0-or-later
  */
@@ -71,6 +71,7 @@ public:
         Command,
         LogFile,
         CommandXTerm,
+        CommandHideError,
 
         EmailSubject,
         EmailFromId,