LibJS: Reorganize tests into subfolders

Author: https://github.com/mattco98
Commit: 4c48c9d69d
Pull-request: https://github.com/SerenityOS/serenity/pull/2681
Reviewed-by: https://github.com/linusg

Libraries/LibJS/Tests/builtins/Object/Object.getOwnPropertyNames.js

@@ -0,0 +1,21 @@
+load("test-common.js");
+
+try {
+    let names = Object.getOwnPropertyNames([1, 2, 3]);
+
+    assert(names.length === 4);
+    assert(names[0] === "0");
+    assert(names[1] === "1");
+    assert(names[2] === "2");
+    assert(names[3] === "length");
+
+    names = Object.getOwnPropertyNames({ foo: 1, bar: 2, baz: 3 });
+    assert(names.length === 3);
+    assert(names[0] === "foo");
+    assert(names[1] === "bar");
+    assert(names[2] === "baz");
+
+    console.log("PASS");
+} catch (e) {
+    console.log("FAIL: " + e);
+}