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
}
    
    protected void hookControl(Control control) {
        super.hookControl(control);
        addTreeListener(control, new TreeListener() {
            public void treeExpanded(TreeEvent event) {
                handleTreeExpand(event);
            }
            public void treeCollapsed(TreeEvent event) {
                handleTreeCollapse(event);
            }
        });
    }
    /*
     * (non-Javadoc) Method declared on StructuredViewer. Builds the initial
     * tree and handles the automatic expand feature.
     */
    protected void inputChanged(Object input, Object oldInput) {
        preservingSelection(new Runnable() {
            public void run() {
                Control tree = getControl();
                boolean useRedraw = true;
                
                
                if (useRedraw)
                    tree.setRedraw(false);
                removeAll(tree);
                tree.setData(getRoot());
                createChildren(tree);
                internalExpandToLevel(tree, expandToLevel);