Added a very complicated AsyncIterableReader class.

The class was already implemented in
"https://deno.land/std@0.144.0/streams/conversion.ts".  So, I litterally
lost 1 day of work!  I hate myself.

vendor/deno.land/std@0.188.0/streams/writer_from_stream_writer.ts

@@ -0,0 +1,35 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+// This module is browser compatible.
+
+import type { Writer } from "../types.d.ts";
+
+/** Create a `Writer` from a `WritableStreamDefaultWriter`.
+ *
+ * @example
+ * ```ts
+ * import { copy } from "https://deno.land/std@$STD_VERSION/streams/copy.ts";
+ * import { writerFromStreamWriter } from "https://deno.land/std@$STD_VERSION/streams/writer_from_stream_writer.ts";
+ *
+ * const file = await Deno.open("./deno.land.html", { read: true });
+ *
+ * const writableStream = new WritableStream({
+ *   write(chunk): void {
+ *     console.log(chunk);
+ *   },
+ * });
+ * const writer = writerFromStreamWriter(writableStream.getWriter());
+ * await copy(file, writer);
+ * file.close();
+ * ```
+ */
+export function writerFromStreamWriter(
+  streamWriter: WritableStreamDefaultWriter<Uint8Array>,
+): Writer {
+  return {
+    async write(p: Uint8Array): Promise<number> {
+      await streamWriter.ready;
+      await streamWriter.write(p);
+      return p.length;
+    },
+  };
+}