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 Widget doFindInputItem(Object element) {
        
        Object root = getRoot();
        if (root == null)
            return null;
        if (equals(root, element))
            return getControl();
        return null;
    }
    
    protected Widget doFindItem(Object element) {
        
        Object root = getRoot();
        if (root == null)
            return null;
        Item[] items = getChildren(getControl());
        if (items != null) {
            for (int i = 0; i < items.length; i++) {
                Widget o = internalFindItem(items[i], element);
                if (o != null)
                    return o;
            }
        }
        return null;
    }
    /**
     * Copies the attributes of the given element into the given SWT item.
     *