colors on anchors are sorted

frontend-js/src/main/js/map/surface/AliasSurface.js

@@ -204,6 +204,10 @@ AliasSurface.prototype._computeColors = function () {
           result.push({color: color, amount: countByColor[color]});
         }
       }
+      var compare = function (a, b) {
+        return a.color.localeCompare(b.color);
+      };
+      result.sort(compare);
       return result;
     });
   }