Bug 17292 Inconsistent Undo behaviour for Cut/Copy/Paste in outline
Build 20020521 (freeze 1) 1) Open a java editor on some class 2) In the content outline, select a method and do Ctrl+X to cut 3) Notice in the menus, Edit->Undo and Refactor->Undo are disabled 4) Now select the type node in the content outline, and Ctrl+V to paste 5) Still, neither Undo action is enabled 6) Now click inside the editor area to give it focus. 7) Now "Edit->Undo" is possible. So, the problems are: 1) Undo is not consistent, it's available for Paste but not Cut. 2) Even when undo is possible, it only becomes enabled when the editor is activated.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaOutlinePage.java
if (fMenu != null && !fMenu.isDisposed()) {
			fMenu.dispose();
			fMenu= null;
		}
		
		if (fActionGroups != null)
			fActionGroups.dispose();
			
		fTogglePresentation.setEditor(null);
		fToggleTextHover.setEditor(null);
		fPreviousError.setEditor(null);
		fNextError.setEditor(null);	
		
		fOutlineViewer= null;
		
		super.dispose();
	}
	
	public Control getControl() {
		if (fOutlineViewer != null)
			return fOutlineViewer.getControl();
		return null;
	}
	
	public void setInput(IJavaElement inputElement) {
		fInput= inputElement;	
		if (fOutlineViewer != null)
			fOutlineViewer.setInput(fInput);
	}