Bug 47838 Make refactoring menu selection sensitive in editor [refactoring]
M5 Currently all refactoring actions are enabled in the editor's context menu. Make them selection dependent. Check if code resolve might be enough (no need to create an AST).
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/RefactorActionGroup.java
private SelectionDispatchAction fExtractTempAction;
	private SelectionDispatchAction fExtractConstantAction;
	private SelectionDispatchAction fIntroduceParameterAction;
	private SelectionDispatchAction fIntroduceFactoryAction;
	private SelectionDispatchAction fConvertLocalToFieldAction;
	private SelectionDispatchAction fSelfEncapsulateField;
	private SelectionDispatchAction fRenameRefactoringAction;
	
	/**
	 * Creates a new <code>RefactorActionGroup</code>. The group requires
	 * that the selection provided by the part's selection provider is of type <code>
	 * org.eclipse.jface.viewers.IStructuredSelection</code>.
	 * 
	 * @param part the view part that owns this action group
	 */
	public RefactorActionGroup(IViewPart part) {
		this(part.getSite());
	}	
	
	/**
	 * Creates a new <code>RefactorActionGroup</code>. The action requires
	 * that the selection provided by the page's selection provider is of type <code>
	 * org.eclipse.jface.viewers.IStructuredSelection</code>.
	 * 
	 * @param page the page that owns this action group
	 */
	public RefactorActionGroup(Page page) {
		this(page.getSite());
	}