qml: fix undefined errors
Errors regarding double-clicking a music album:
qml message qrc:/widgets/KeyNavigableTableView.qml:338 Unable to assign [undefined] to QString
qml message qrc:/medialibrary/MusicAlbumsGridExpandDelegate.qml:146 ReferenceError: expand_cover_id is not defined
qml message qrc:/widgets/KeyNavigableTableView.qml:338 Unable to assign [undefined] to QString
qml message qrc:/medialibrary/MusicAlbumsGridExpandDelegate.qml:275 QML RowLayout: Binding loop detected for property "height"
Edited by Leon Vitanos