Fix for react-tests in Debug

lib/browser/index.js

@@ -175,6 +175,11 @@ Object.defineProperties(Realm, {
             rpc.clearTestState();
         },
     },
+    _waitForDownload: {
+        value: function(_config) {
+            return rpc.callMethod(undefined, Realm[keys.id], '_waitForDownload', Array.from(arguments));
+        }
+    },
 });
 
 for (let i = 0, len = debugHosts.length; i < len; i++) {