Fix QGeoMapObject handling in reference implementation

setVisible was neither changing the visibility nor
triggering repaint.
Pimpls weren't removing themselves in their destructors when
dynamically added/removed via QGeoMapObjectView
add/removeMapObject.
This patch also factors out the duplicated QGeoMapObject support
from QGeoTiledMapLabs and QGeoMapObjectsOverlay and moves it
into an own class, QGeoMapObjectQSGSupport.
To properly flush the scene graph nodes upon object removal,
a pointer to the QSGNode is added to the MapObject struct,
now moved inside QGeoMapObjectQSGSupport.

Change-Id: Ie8c6d54f8f340ba3867717d9620791d3fe8021cc
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>

1 files changed, 2 insertions, 1 deletions

diff --git a/src/location/labs/qmappolylineobject.cpp b/src/location/labs/qmappolylineobject.cpp
index bea79327..1c351962 100644
--- a/src/location/labs/qmappolylineobject.cpp
+++ b/src/location/labs/qmappolylineobject.cpp
@@ -209,7 +209,8 @@ void QMapPolylineObject::setMap(QGeoMap *map)
     QGeoMapObject::setMap(map); // This is where the specialized pimpl gets created and injected
 
     if (!map) {
-        // Map was set, now it has ben re-set to NULL
+        // Map was set, now it has ben re-set to NULL, but not inside d_ptr.
+        // so m_map inside d_ptr can still be used to remove itself, inside the destructor.
         d_ptr = new QMapPolylineObjectPrivateDefault(*d);
         // Old pimpl deleted implicitly by QExplicitlySharedDataPointer
     }