lib,url: correct URL's argument to pass idlharness

`url.idl` defines URL's constructor as:

```
constructor(USVString url, optional USVString base);
```

`idlharness.any.js` checks its length as `1`. So we should remove
constructor's second argument and use `arguments[1]` in constructor's
logic.

Refs: https://url.spec.whatwg.org/#idl-index

lib/internal/url.js

@@ -621,7 +621,7 @@ function isURLThis(self) {
 }
 
 class URL {
-  constructor(input, base) {
+  constructor(input, base = undefined) {
     // toUSVString is not needed.
     input = `${input}`;
     let base_context;

test/common/wpt.js

@@ -288,6 +288,7 @@ class WPTRunner {
     this.resource = new ResourceLoader(path);
 
     this.flags = [];
+    this.dummyGlobalThisScript = null;
     this.initScript = null;
 
     this.status = new StatusLoader(path);
@@ -318,6 +319,43 @@ class WPTRunner {
     this.initScript = script;
   }
 
+  get fullInitScript() {
+    if (this.initScript === null && this.dummyGlobalThisScript === null) {
+      return null;
+    }
+
+    if (this.initScript === null) {
+      return this.dummyGlobalThisScript;
+    } else if (this.dummyGlobalThisScript === null) {
+      return this.initScript;
+    }
+
+    return `${this.fullInitScript}\n\n//===\n${this.initScript}`;
+  }
+
+  /**
+   * Pretend the runner is run in `name`'s environment (globalThis).
+   * @param {'Window'} name
+   * @see {@link https://github.com/nodejs/node/blob/24673ace8ae196bd1c6d4676507d6e8c94cf0b90/test/fixtures/wpt/resources/idlharness.js#L654-L671}
+   */
+  pretendGlobalThisAs(name) {
+    switch (name) {
+      case 'Window': {
+        this.dummyGlobalThisScript =
+          'global.Window = Object.getPrototypeOf(globalThis).constructor;';
+        break;
+      }
+
+      // TODO(XadillaX): implement `ServiceWorkerGlobalScope`,
+      // `DedicateWorkerGlobalScope`, etc.
+      //
+      // e.g. `ServiceWorkerGlobalScope` should implement dummy
+      // `addEventListener` and so on.
+
+      default: throw new Error(`Invalid globalThis type ${name}.`);
+    }
+  }
+
   // TODO(joyeecheung): work with the upstream to port more tests in .html
   // to .js.
   runJsTests() {
@@ -368,7 +406,7 @@ class WPTRunner {
           testRelativePath: relativePath,
           wptRunner: __filename,
           wptPath: this.path,
-          initScript: this.initScript,
+          initScript: this.fullInitScript,
           harness: {
             code: fs.readFileSync(harnessPath, 'utf8'),
             filename: harnessPath,

test/wpt/status/url.json

@@ -13,9 +13,6 @@
   "urlencoded-parser.any.js": {
     "fail": "missing Request and Response"
   },
-  "idlharness.any.js": {
-    "fail": "getter/setter names are wrong, etc."
-  },
   "urlsearchparams-constructor.any.js": {
     "fail": "FormData is not defined"
   },

test/wpt/test-url.js

@@ -5,4 +5,5 @@ const { WPTRunner } = require('../common/wpt');
 
 const runner = new WPTRunner('url');
 
+runner.pretendGlobalThisAs('Window');
 runner.runJsTests();