Bug 100565 [Viewers] Tree viewer selection not revealed if unchanged
[RC3] Steps: 1. Check out org.eclipse.ui.workbench 2. Open Workbench.java 3. Ctrl-O to open Quick Outline 4. Type "r", note that the field "runEventLoop" is the first match 5. Type "u", note that the field is not shown anymore 6. Type arrow-down key, note that you cannot see the selected entry
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
*/
    public void addTreeListener(ITreeViewerListener listener) {
        treeListeners.add(listener);
    }
    /**
     * Adds the given SWT tree listener to the given SWT control.
     * 
     * @param control
     *           the SWT control
     * @param listener
     *           the SWT tree listener
     */
    protected abstract void addTreeListener(Control control,
            TreeListener listener);
    
    protected void associate(Object element, Item item) {
        Object data = item.getData();
        if (data != null && data != element && equals(data, element)) {
            
            
            
            unmapElement(data, item);
            item.setData(element);
            mapElement(element, item);
        } else {
            
            super.associate(element, item);
        }
    }
    /**