track: emit virtual height rather than pixel height

app/node/output/track/track.cpp

@@ -180,7 +180,7 @@ const double &Track::GetTrackHeight() const
 void Track::SetTrackHeight(const double &height)
 {
   track_height_ = height;
-  emit TrackHeightChangedInPixels(GetTrackHeightInPixels());
+  emit TrackHeightChanged(track_height_);
 }
 
 void Track::InputConnectedEvent(const QString &input, int element, Node *output)

app/node/output/track/track.h

@@ -425,7 +425,7 @@ signals:
   /**
    * @brief Signal emitted when the height of the track has changed
    */
-  void TrackHeightChangedInPixels(int pixel_height);
+  void TrackHeightChanged(qreal virtual_height);
 
   /**
    * @brief Signal emitted when the muted setting changes

app/node/output/track/tracklist.cpp

@@ -81,8 +81,9 @@ void TrackList::TrackConnected(Node *node, int element)
   UpdateTrackIndexesFrom(cache_index);
 
   connect(track, &Track::TrackLengthChanged, this, &TrackList::UpdateTotalLength);
-  connect(track, &Track::TrackHeightChangedInPixels, this, [this](int height){
-    emit TrackHeightChanged(static_cast<Track*>(sender()), height);
+  connect(track, &Track::TrackHeightChanged, this, [this](){
+    Track *t = static_cast<Track*>(sender());
+    emit TrackHeightChanged(t, t->GetTrackHeightInPixels());
   });
 
   track->set_type(type_);