Bug 305004 The PathVariableSelectionDialog should not use 'Extend' to build path variable arguments
The PathVariableSelectionDialog should not use 'Extend' to build path variable arguments, since this is used already to build a path, which could be used to build a path starting off an argumented path variable.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/dialogs/PathVariableSelectionDialog.java
* <pre>
 *  PathVariableSelectionDialog dialog =
 *    new PathVariableSelectionDialog(getShell(), IResource.FOLDER);
 *	dialog.open();
 *	String[] result = (String[]) dialog.getResult();
 * </pre> 	
 * </p>
 * 
 * @since 3.1
 */
public final class PathVariableSelectionDialog extends SelectionDialog {
    private static final int EXTEND_ID = IDialogConstants.CLIENT_ID + 1;
    private PathVariablesGroup pathVariablesGroup;
	private IResource currentResource = null;
    private int variableType;
    /**
     * Creates a path variable selection dialog.
     *
     * @param parentShell the parent shell
     * @param variableType the type of variables that are displayed in 
     * 	this dialog. <code>IResource.FILE</code> and/or <code>IResource.FOLDER</code>
     * 	logically ORed together.
     */
    public PathVariableSelectionDialog(Shell parentShell, int variableType) {
        super(parentShell);
        setTitle(IDEWorkbenchMessages.PathVariableSelectionDialog_title);
        this.variableType = variableType;
        pathVariablesGroup = new PathVariablesGroup(false, variableType,
                new Listener() {
                    /* (non-Javadoc)