Bug 92988 [Viewers] potential NPE in AbstractTreeViewer
I0426, found with FindBugs 1. AbstractTreeViewer line 832 invokes "siblings.length", but the "if" statement above implies that siblings could be null here. 2. StringFieldEditor line 187 does an unnecessary null check since Text.getText() never returns null (FindBugs was using this to point to line 190 as a potential NPE).
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
* @param widget
     *           the widget
     * @param element
     *           the element
     * @param doStruct
     *           <code>true</code> if structural changes are to be picked up,
     *           and <code>false</code> if only label provider changes are of
     *           interest
     * @param updateLabels
     *           <code>true</code> to update labels for existing elements,
     *           <code>false</code> to only update labels as needed, assuming
     *           that labels for existing elements are unchanged.
     * @since 3.1
     */
    protected void internalRefresh(Widget widget, Object element,
            boolean doStruct, boolean updateLabels) {
        if (widget instanceof Item) {
            if (doStruct) {
                updatePlus((Item) widget, element);
            }
            if (updateLabels || !equals(element, widget.getData())) {
                doUpdateItem(widget, element, true);
            } else {
                associate(element, (Item) widget);
            }
        }
        if (doStruct) {
            internalRefreshStruct(widget, element, updateLabels);
        } else {
            Item[] children = getChildren(widget);