Bug 40788 [plan item] Configurable Next/Previous actions
Toolbar drop down, or editor specific control. Needs to be coordinated with Platform UI.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaEditor.java
changeColumn.redraw();
	}
	
	/**
	 * Creates a new change ruler column for quick diff display independent of the 
	 * line number ruler column
	 * 
	 * @return a new change ruler column
	 * @since R3.0
	 */
	protected IChangeRulerColumn createChangeRulerColumn() {
		IChangeRulerColumn column= new ChangeRulerColumn();
		column.setHover(new JavaChangeHover());
		fChangeRulerColumn= column;
		initializeChangeRulerColumn(fChangeRulerColumn);
		return fChangeRulerColumn;
	}
	
	/*
	 * @see AbstractTextEditor#createVerticalRuler()
	 */
	protected IVerticalRuler createVerticalRuler() {
		CompositeRuler ruler= new CompositeRuler();
		ruler.addDecorator(0, new AnnotationRulerColumn(VERTICAL_RULER_WIDTH));
		
		if (isLineNumberRulerVisible())
			ruler.addDecorator(1, createLineNumberRulerColumn());
		else if (isQuickDiffAlwaysOn())
			ruler.addDecorator(1, createChangeRulerColumn());