Bug 17423 Revert apears twice in the popup menu.
Build F1. 1) Open a java editor. 2) Popup the menu. There is only one Revert option disable as it should be. 3) Make the editor dirty. 4) Popup the menu. There are two Revert option in the menu. One after UNDO and other before FORMAT.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
* Jumps to the error next according to the given direction.
	 */
	public void gotoError(boolean forward) {
		
		ISelectionProvider provider= getSelectionProvider();
		
		if (fStatusLineClearer != null) {
			provider.removeSelectionChangedListener(fStatusLineClearer);
			fStatusLineClearer= null;
		}
		
		ITextSelection s= (ITextSelection) provider.getSelection();
		Position errorPosition= new Position(0, 0);
		IProblemAnnotation nextError= getNextError(s.getOffset(), forward, errorPosition);
		
		if (nextError != null) {
			
			selectAndReveal(errorPosition.getOffset(), errorPosition.getLength());
			
			IMarker marker= null;
			if (nextError instanceof MarkerAnnotation)
				marker= ((MarkerAnnotation) nextError).getMarker();
			else {
				Iterator e= nextError.getOverlaidIterator();
				if (e != null) {
					while (e.hasNext()) {
						Object o= e.next();
						if (o instanceof MarkerAnnotation) {
							marker= ((MarkerAnnotation) o).getMarker();
							break;