Added debugging mode for simultaneous QML and C++ debugging

It's not yet possible to attach to an external app running a qml
debugging server, because the server is only started on startup if an
env variable is set. Changing this requires action from Brisbane, but
even the current solution works for C++ apps with QML in them.

Task-number: BAUHAUS-585
Reviewed-by: dt

src/plugins/debugger/debuggeruiswitcher.cpp

@@ -263,9 +263,12 @@ void DebuggerUISwitcher::addLanguage(const QString &langName, const QList<int> &
 
     d->m_languageActionGroup->addAction(langChange);
 
+    QString prefix = tr("Alt+L");
     connect(langChange, SIGNAL(triggered()), SLOT(langChangeTriggered()));
     Core::Command *cmd = am->registerAction(langChange,
                          "Debugger.Language." + langName, d->m_globalContext);
+    cmd->setDefaultKeySequence(QKeySequence(QString("%1,%2").arg(prefix, QString::number(d->m_languages.count()))));
+
     d->m_languageMenu->addAction(cmd);
 }