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
return null;
    }
    
    protected void internalRefresh(Object element) {
        internalRefresh(element, true);
    }
    
    protected void internalRefresh(Object element, boolean updateLabels) {
        
        if (element == null) {
            internalRefresh(getControl(), getRoot(), true, updateLabels);
            return;
        }
        Widget item = findItem(element);
        if (item != null) {
            
            internalRefresh(item, element, true, updateLabels);
        }
    }
    /**
     * Refreshes the tree starting at the given widget.
     * <p>
     * EXPERIMENTAL.  Not to be used except by JDT.
     * This method was added to support JDT's explorations
     * into grouping by working sets, which requires viewers to support multiple 
     * equal elements.  See bug 76482 for more details.  This support will
     * likely be removed in Eclipse 3.2 in favour of proper support for
     * multiple equal elements. 
     * </p>
     *