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
public boolean isVerticalRulerVisible() {
			return fCachedIsVerticalRulerVisible;
		}
		
		public OverviewRuler getOverviewRuler() {
			return fOverviewRuler;
		}
		
		/*
		 * @see TextViewer#createControl(Composite, int)
		 */
		protected void createControl(Composite parent, int styles) {
			
		}
		
		protected void delayedCreateControl(Composite parent, int styles) {
			
			super.createControl(parent, styles);
			
			Control control= getControl();
			if (control instanceof Composite) {
				Composite composite= (Composite) control;
				composite.setLayout(new AdaptedRulerLayout(GAP_SIZE, this));
				fOverviewRuler.createControl(composite, this);
			}
		}
		
		public void hideOverviewRuler() {
			fIsOverviewRulerVisible= false;