opacity is passed properly

frontend-js/src/main/js/map/marker/MarkerSurfaceCollection.js

@@ -202,7 +202,7 @@ MarkerSurfaceCollection.prototype.createSurfaceForDbOverlay = function (element,
         map: map,
         onClick: onclickFunctions,
         color: element.getColor(),
-        fillOpacity: element.getOpacity(),
+        opacity: element.getOpacity(),
         strokeWeight: element.getLineWeight(),
         strokeColor: element.getLineColor(),
         strokeOpacity: element.getLineOpacity()

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

@@ -31,6 +31,11 @@ var Point = require('../canvas/Point');
  * @param {IdentifiedElement} [params.element]
  * @param {Alias} params.alias
  * @param {AbstractCustomMap} params.map
+ * @param {string} [params.color]
+ * @param {number} [params.opacity]
+ * @param {number} [params.strokeWeight]
+ * @param {string} [params.strokeColor]
+ * @param {number} [params.strokeOpacity]
  * @param {function|function[]} [params.onClick]
  * @constructor
  * @extends AbstractSurfaceElement
@@ -38,9 +43,6 @@ var Point = require('../canvas/Point');
 function AliasSurface(params) {
   // call super constructor
   AbstractSurfaceElement.call(this, params);
-  if (params.overlayAlias !== undefined) {
-    throw new Error();
-  }
 
   this.setOverlayData(params.overlayData);
   this.setStartX(params.startX);
@@ -187,7 +189,7 @@ AliasSurface.prototype._computeColors = function () {
   var self = this;
   var overlayData = self.getOverlayData();
   if (overlayData === undefined || overlayData.length === 0) {
-    return self.getColor();
+    return Promise.resolve(self.getColor());
   } else {
     return functions.overlaysToColorDataStructure(overlayData);
   }