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 v.toArray();
    }
    /**
     * Returns whether the node corresponding to the given element is expanded
     * or collapsed.
     * 
     * @param element
     *           the element
     * @return <code>true</code> if the node is expanded, and <code>false</code>
     *         if collapsed
     */
    public boolean getExpandedState(Object element) {
        Assert.isNotNull(element);
        Widget item = findItem(element);
        if (item instanceof Item)
            return getExpanded((Item) item);
        return false;
    }
    /**
     * Returns the number of child items of the given SWT control.
     * 
     * @param control
     *           the control
     * @return the number of children
     */
    protected abstract int getItemCount(Control control);
    /**
     * Returns the number of child items of the given SWT item.
     * 
     * @param item