Shortcut settings: Update collision markers when resetting shortcut

Task-number: QTCREATORBUG-6400

Change-Id: Ibef1da2fb71d157769412d7cbbd730e7656979ed
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/coreplugin/dialogs/shortcutsettings.cpp

@@ -200,6 +200,8 @@ void ShortcutSettings::resetTargetIdentifier()
     if (current && current->data(0, Qt::UserRole).isValid()) {
         ShortcutItem *scitem = qvariant_cast<ShortcutItem *>(current->data(0, Qt::UserRole));
         setKeySequence(scitem->m_cmd->defaultKeySequence());
+        foreach (ShortcutItem *item, m_scitems)
+            markCollisions(item);
     }
 }