Use ol.object.assign() instead of goog.object.clone()

src/ol/map.js

@@ -44,6 +44,7 @@ goog.require('ol.has');
 goog.require('ol.interaction');
 goog.require('ol.layer.Base');
 goog.require('ol.layer.Group');
+goog.require('ol.object');
 goog.require('ol.proj');
 goog.require('ol.proj.common');
 goog.require('ol.renderer.Map');
@@ -1325,7 +1326,7 @@ ol.Map.prototype.renderFrame_ = function(time) {
       index: this.frameIndex_++,
       layerStates: layerStates,
       layerStatesArray: layerStatesArray,
-      logos: goog.object.clone(this.logos_),
+      logos: ol.object.assign({}, this.logos_),
       pixelRatio: this.pixelRatio_,
       pixelToCoordinateMatrix: this.pixelToCoordinateMatrix_,
       postRenderFunctions: [],