perf(ext/web): optimize structuredClone without transferables (#20730)

This PR optimizes `structuredClone` when it's called without
transferables.

### Benchmarks

**main**
```
cpu: 13th Gen Intel(R) Core(TM) i9-13900H
runtime: deno 1.37.1 (x86_64-unknown-linux-gnu)

benchmark                          time (avg)        iter/s             (min … max)       p75       p99      p995
----------------------------------------------------------------------------------- -----------------------------
structuredClone object              1.64 µs/iter     611,086.0     (1.58 µs … 1.84 µs)   1.66 µs   1.84 µs   1.84 µs
structuredClone transferables       2.82 µs/iter     354,281.4     (2.78 µs … 2.92 µs)   2.84 µs   2.92 µs   2.92 µs
```

**this PR**

```
cpu: 13th Gen Intel(R) Core(TM) i9-13900H
runtime: deno 1.37.1 (x86_64-unknown-linux-gnu)

structuredClone object                 1 µs/iter     998,383.5    (971.28 ns … 1.2 µs)      1 µs    1.2 µs    1.2 µs
structuredClone transferables       2.82 µs/iter     355,087.5      (2.7 µs … 3.07 µs)   2.83 µs   3.07 µs   3.07 µs
```

```js
Deno.bench("structuredClone object", () => {
  structuredClone({ foo: "bar" });
});

Deno.bench("structuredClone transferables", () => {
  const buf = new Uint8Array([97]);
  structuredClone(buf, {
    transfer: [buf.buffer],
  });
});
```

0 files changed, 0 insertions, 0 deletions