Bug 121034 [jar import] Cancel should undo all already executed refactorings
3.2 M4
org.eclipse.ltk.ui.refactoring/src/org/eclipse/ltk/ui/refactoring/history/RefactoringHistoryWizard.java
*            the refactoring descriptor
	 * @param monitor
	 *            the progress monitor to use
	 * @return a status describing the outcome of the initialization
	 */
	protected RefactoringStatus aboutToPerformRefactoring(final Refactoring refactoring, final RefactoringDescriptor descriptor, final IProgressMonitor monitor) {
		Assert.isNotNull(refactoring);
		Assert.isNotNull(descriptor);
		return new RefactoringStatus();
	}
	/**
	 * {@inheritDoc}
	 * 
	 * Clients must contribute their wizard pages by re-implementing
	 * {@link #addUserDefinedPages()}.
	 */
	public final void addPage(final IWizardPage page) {
		Assert.isTrue(fInAddPages);
		super.addPage(page);
	}
	/**
	 * {@inheritDoc}
	 */
	public final void addPages() {
		try {
			fInAddPages= true;
			addUserDefinedPages();
			Assert.isNotNull(fRefactoringHistory);
			Assert.isNotNull(fControlConfiguration);
			if (fShowOverview) {