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
/**
     * Constant indicating that all levels of the tree should be expanded or
     * collapsed.
     * 
     * @see #expandToLevel
     * @see #collapseToLevel
     */
    public static final int ALL_LEVELS = -1;
    /**
     * List of registered tree listeners (element type: <code>TreeListener</code>). */
    private ListenerList treeListeners = new ListenerList(1);
    /**
     * The level to which the tree is automatically expanded each time the
     * viewer's input is changed (that is, by <code>setInput</code>). A
     * value of 0 means that auto-expand is off.
     * 
     * @see #setAutoExpandLevel
     */
    private int expandToLevel = 0;
    /**
     * Safe runnable used to update an item.
     */
    class UpdateItemSafeRunnable extends SafeRunnable {