removing data overlay works properly

frontend-js/src/main/js/gui/leftPanel/OverlayPanel.js

@@ -711,6 +711,7 @@ OverlayPanel.prototype.removeOverlay = function (overlay) {
   return self.getMap().hideDataOverlay(overlay.getId()).then(function () {
     return self.getServerConnector().removeOverlay({overlayId: overlay.getId()});
   }).then(function () {
+    self.getProject().removeDataOverlay(overlay);
     return self.refresh();
   })
 };

frontend-js/src/main/js/map/data/Project.js

@@ -456,6 +456,19 @@ Project.prototype.addDataOverlay = function (overlay, updateWhenExists) {
   }
 };
 
+/**
+ *
+ * @param {DataOverlay} overlay
+ */
+Project.prototype.removeDataOverlay = function (overlay) {
+  var object = this._dataOverlays[overlay.getId()];
+  if (object === undefined) {
+    throw new Error("Overlay " + overlay.getId() + " doesn't exist in a project " + this.getProjectId());
+  } else {
+    delete this._dataOverlays[overlay.getId()];
+  }
+};
+
 /**
  *
  * @param {DataOverlay} overlay