code: public void onDeselectLayer(LayerDeselectedEvent event) {
  		ListGridRecord selected = treeGrid.getSelectedRecord();
  		if (selected != null) {
  			treeGrid.deselectRecord(selected);
  		}
  		selectedLayerTreeNode = null;
  		htmlSelectedLayer.setContents(I18nProvider.getLayerTree().activeLayer(I18nProvider.getLayerTree().none()));
  	}
docs: When a layer deselection event comes in, the LayerTree must also deselect the correct node in the tree, update
  the selected layer text, and update all buttons icons.
  
  @param event
  event