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/preference/StringFieldEditor.java
*
     * @see #setValidateStrategy
     */
    public static final int VALIDATE_ON_FOCUS_LOST = 1;
    /**
     * Text limit constant (value <code>-1</code>) indicating unlimited
     * text limit and width.
     */
    public static int UNLIMITED = -1;
    /**
     * Cached valid state.
     */
    private boolean isValid;
    /**
     * Old text value.
     */
    private String oldValue;
    /**
     * The text field, or <code>null</code> if none.
     */
    Text textField;
    /**
     * Width of text field in characters; initially unlimited.
     */
    private int widthInChars = UNLIMITED;
    /**
     * Text limit of text field in characters; initially unlimited.
     */
    private int textLimit = UNLIMITED;
    /**