Bug 33040 No single Undo for generate delegate methods
RC 1 - JUnit setup - open TestCase - select fName - generate delegate methods for all String methods - press Ctrl+Z Observe: only one method is removed.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/OverrideMethodsAction.java
private boolean checkEnabledEditor() {
		return fEditor != null && SelectionConverter.canOperateOn(fEditor);
	}
	/* (non-Javadoc)
	 * Method declared on SelectionDispatchAction
	 */
	protected void run(ITextSelection selection) {
		Shell shell= getShell();
		try {
			IType type= SelectionConverter.getTypeAtOffset(fEditor);
			if (type != null) {
				if (!ElementValidator.check(type, shell, getDialogTitle(), false) || !ActionUtil.isProcessable(shell, type)) {
					return;
				}						
				run(shell, type, fEditor);
			} else {
				MessageDialog.openInformation(shell, getDialogTitle(), ActionMessages.getString("OverrideMethodsAction.not_applicable")); 
			}
		} catch (JavaModelException e) {
			ExceptionHandler.handle(e, getShell(), getDialogTitle(), null);
		}
	}
	
	
	private void run(Shell shell, IType type, IEditorPart editor) {
		OverrideMethodQuery selectionQuery= new OverrideMethodQuery(shell, false);
		CodeGenerationSettings settings= JavaPreferencesSettings.getCodeGenerationSettings();
		AddUnimplementedMethodsOperation op= new AddUnimplementedMethodsOperation(type, settings, selectionQuery, false);
		try {