Bug 310446 [LinkedResources] "Preferences > Linked Resources > New..." should not show "Variable..."
I20100425-2000 "Preferences > Linked Resources": The "New..." and "Edit..." dialogs should not show the "Variable..." button. When I select a variable, the "New Variable" dialog show an error (Path must be absolute.), and when I try to click "Extend...", nothing happens.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/PathVariableDialog.java
*/
    private IPathVariableManager pathVariableManager;
    /**
     * Set of variable names currently in use. Used when warning the user that
     * the currently selected name is already in use by another variable.
     */
    private Set namesInUse;
    /**
     * The current validation status. Its value can be one of the following:<ul>
     * <li><code>IMessageProvider.NONE</code> (default);</li>
     * <li><code>IMessageProvider.WARNING</code>;</li>
     * <li><code>IMessageProvider.ERROR</code>;</li>
     * </ul>
     * Used when validating the user input.
     */
    private int validationStatus;
    /**
     * The current validation message generated by the last
     * call to a <code>validate</code> method.
     */
    private String validationMessage;
    /**
     * Whether a variable name has been entered.  
     */
    private boolean nameEntered = false;
    /**
     * Whether a variable location has been entered.  
     */
    private boolean locationEntered = false;
    /**