TVB-2887: Solved bug related to TimeSeriesVolumeVisualiser

Created by: VinczeRobert

This problem had two sources. The first one is what Paula described on the task and the second one was that prepare_view_region from region_volume_mapping is called twice and both times self was TimeSeriesVolumeVisualizer, but the second time it actually should have been different so the get_view_region from region_volume_mapping is called. That is why I changed the stored adapter in the launch method.