Bug 125272 [Viewers] AbstractTreeViewer needs remove(Object parentElement, Object[] childElements)
There is an add(Object parentElement, Object[] childElements) but no corresponding remove(). Without this method, if you have an element that appears under multiple parents, the only way to get model and viewer in sync after removing the element from just one of its parents is calling refresh().
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
*           list of items (element type: <code>org.eclipse.swt.widgets.Item</code>)
     */
    protected abstract void setSelection(List items);
    /**
     *  This implementation of setSelectionToWidget accepts a list of elements
     *  or a list of tree paths.
     **/
    protected void setSelectionToWidget(List v, boolean reveal) {
        if (v == null) {
            setSelection(new ArrayList(0));
            return;
        }
        int size = v.size();
        List newSelection = new ArrayList(size);
        for (int i = 0; i < size; ++i) {
            
            
            Widget w = internalExpand(v.get(i), false);
            if (w instanceof Item) {
                newSelection.add(w);
            }
        }
        setSelection(newSelection);
        
        
        
        
        
        if (reveal && newSelection.size() > 0) {
            showItem((Item) newSelection.get(0));