8287094: IGV: show node input numbers in edge tooltips

Reviewed-by: chagedorn, thartmann

src/utils/IdealGraphVisualizer/Graph/src/main/java/com/sun/hotspot/igv/graph/FigureConnection.java

@@ -105,6 +105,9 @@ public class FigureConnection implements Connection {
         builder.append(getOutputSlot().getFigure().getProperties().resolveString(shortNodeText));
         builder.append(" → ");
         builder.append(getInputSlot().getFigure().getProperties().resolveString(shortNodeText));
+        builder.append(" [")
+               .append(getInputSlot().getPosition())
+               .append("]");
         return builder.toString();
     }