Bug 72024 UndoManager creates potential memory leak [refactoring]
3.0 The refactoring undo manager doesn't call dispose in all cases where a undo/redo object is no longer needed. This can result in a memory leak since the undo/redo object could register for listeners and therefore relies on the fact the dispose is called correctly. Cases where dispose isn't called: - if the undo stack reaches it maximum number of change objects and the last one is removed from the stack. - if the undo/redo stack gests flushed and one of the change objects causes an exception during sending dispose. - if the undo/redo object isn't valid anymore and can therefore not be executed.
org.eclipse.ltk.ui.refactoring/src/org/eclipse/ltk/internal/ui/refactoring/RefactoringWizardDialog2.java
if (defaultButton != null) {
			defaultButton.getShell().setDefaultButton(defaultButton);
		}
	}
	/* (non-Javadoc)
	 * Method declared on IWizardContainer.
	 */
	public void updateMessage() {
		if (fStatusContainer == null || fStatusContainer.isDisposed())
			return;
		fStatusContainer.showPage(fMessageBox);
		fMessageBox.setMessage(fCurrentPage);
	}
	/* (non-Javadoc)
	 * Method declared on IWizardContainer.
	 */
	public void updateTitleBar() {
		
	}
	/* (non-Javadoc)
	 * Method declared on IWizardContainer.
	 */
	public void updateWindowTitle() {
		getShell().setText(fWizard.getWindowTitle());
	}
	/* (non-Javadoc)
	 * Method declared on IWizardContainer.
	 */
	public IWizardPage getCurrentPage() {
		return fCurrentPage;