LibJS: Add ArrayBuffer

Author: https://github.com/linusg
Commit: https://github.com/SerenityOS/serenity/commit/32571dfa538
Pull-request: https://github.com/SerenityOS/serenity/pull/4307

Libraries/LibJS/Tests/builtins/ArrayBuffer/ArrayBuffer.js

@@ -0,0 +1,13 @@
+test("basic functionality", () => {
+    expect(ArrayBuffer).toHaveLength(1);
+    expect(ArrayBuffer.name).toBe("ArrayBuffer");
+    expect(ArrayBuffer.prototype.constructor).toBe(ArrayBuffer);
+    expect(new ArrayBuffer()).toBeInstanceOf(ArrayBuffer);
+    expect(typeof new ArrayBuffer()).toBe("object");
+});
+
+test("ArrayBuffer constructor must be invoked with 'new'", () => {
+    expect(() => {
+        ArrayBuffer();
+    }).toThrowWithMessage(TypeError, "ArrayBuffer constructor must be called with 'new'");
+});