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
private boolean isBracketHighlightingEnabled() {
		IPreferenceStore store= getPreferenceStore();
		return store.getBoolean(MATCHING_BRACKETS);
	}
	
	private void startLineHighlighting() {
		if (fLinePainter == null) {
			ISourceViewer sourceViewer= getSourceViewer();
			fLinePainter= new LinePainter(sourceViewer);
			fLinePainter.setHighlightColor(getColor(CURRENT_LINE_COLOR));
			fPaintManager.addPainter(fLinePainter);
		}
	}
	
	private void stopLineHighlighting() {
		if (fLinePainter != null) {
			fPaintManager.removePainter(fLinePainter);
			fLinePainter.deactivate(true);
			fLinePainter.dispose();
			fLinePainter= null;
		}
	}
	
	private boolean isLineHighlightingEnabled() {
		IPreferenceStore store= getPreferenceStore();
		return store.getBoolean(CURRENT_LINE);
	}
	
	private void showPrintMargin() {