Two more simple tests

test/built-ins/Object/fromEntries/empty-iterable.js

+// Copyright (C) 2018 Kevin Gibbons. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: When given an empty list, makes an empty object.
+esid: sec-object.fromentries
+features: [Object.fromEntries]
+---*/
+
+var result = Object.fromEntries([]);
+assert.sameValue(Object.keys(result).length, 0);

test/built-ins/Object/fromEntries/prototype.js

+// Copyright (C) 2018 Kevin Gibbons. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Created objects inherit from Object.prototype.
+esid: sec-object.fromentries
+features: [Object.fromEntries]
+---*/
+
+var result = Object.fromEntries([]);
+assert.sameValue(Object.getPrototypeOf(result), Object.prototype);