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
protected void internalExpandToLevel(Widget widget, int level) {
        if (level == ALL_LEVELS || level > 0) {
            createChildren(widget);
            if (widget instanceof Item)
                setExpanded((Item) widget, true);
            if (level == ALL_LEVELS || level > 1) {
                Item[] children = getChildren(widget);
                if (children != null) {
                    int newLevel = (level == ALL_LEVELS ? ALL_LEVELS
                            : level - 1);
                    for (int i = 0; i < children.length; i++)
                        internalExpandToLevel(children[i], newLevel);
                }
            }
        }
    }
    /**
     * Non-recursively tries to find the given element as a child of the given
     * parent item.
     * 
     * @param parent
     *           the parent item
     * @param element
     *           the element
     * @return Widget
     */
    private Widget internalFindChild(Item parent, Object element) {
        Item[] items = getChildren(parent);
        for (int i = 0; i < items.length; i++) {
            Item item = items[i];