Fixed tests

src/common/dom_helper.js

@@ -12,10 +12,9 @@ const windowObjects = [
 ];
 
 const DOMHelper = windowObjects.reduce((result, obj) => {
-    return {
-        ...result,
+    return Object.assign({}, result, {
         [obj]: obj in windowRef ? windowRef[obj] : () => {}
-    };
+    });
 }, {});
 
 DOMHelper.setObject = (key, value) => {

src/reader/ean_reader.js

@@ -324,15 +324,14 @@ EANReader.prototype._decode = function() {
         }
     }
 
-    return {
+    return Object.assign({
         code: result.join(""),
         start: startInfo.start,
         end: code.end,
         codeset: "",
         startInfo: startInfo,
         decodedCodes: decodedCodes,
-        ...resultInfo
-    };
+    }, resultInfo);
 };
 
 EANReader.prototype._decodeExtensions = function(offset) {

src/scanner.js

@@ -345,13 +345,9 @@ function createScanner() {
     }
 
     function configForWorker(config) {
-        return {
-            ...config,
-            inputStream: {
-                ...config.inputStream,
-                target: null
-            }
-        };
+        return Object.assign({}, config, {
+            inputStream: Object.assign({}, config.inputStream, {target: null})
+        });
     }
 
     function workerInterface(factory) {