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
}
    /**
     * Creates an abstract tree viewer. The viewer has no input, no content
     * provider, a default label provider, no sorter, no filters, and has
     * auto-expand turned off.
     */
    protected AbstractTreeViewer() {
        
    }
    /**
     * Adds the given child elements to this viewer as children of the given
     * parent element. If this viewer does not have a sorter, the elements are
     * added at the end of the parent's list of children in the order given;
     * otherwise, the elements are inserted at the appropriate positions.
     * <p>
     * This method should be called (by the content provider) when elements
     * have been added to the model, in order to cause the viewer to accurately
     * reflect the model. This method only affects the viewer, not the model.
     * </p>
     * 
     * @param parentElement
     *           the parent element
     * @param childElements
     *           the child elements to add
     */
    public void add(Object parentElement, Object[] childElements) {
        Assert.isNotNull(parentElement);
        assertElementsNotNull(childElements);
        Widget widget = findItem(parentElement);