stream: use the ring buffer for pending BYOB pull-into descriptors

The byte controller's [[pendingPullIntos]] list was still a plain array
consumed with ArrayPrototypeShift, while every other per-chunk queue in
the WHATWG streams implementation has moved to the Queue ring buffer.
BYOB reads push and shift one descriptor per read, and Array.prototype
shift has real per-call cost even at length 1.
Back the descriptor list with the same lazily materialized Queue used
for the request queues, so constructing a byte stream still allocates
no descriptor storage.
Signed-off-by: Matteo Collina <hello@matteocollina.com>
PR-URL: #64818
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Paolo Insogna <paolo@cowtech.it>
Reviewed-By: Aviv Keller <me@aviv.sh>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>

Author: mcollina

benchmark/webstreams/tee.js

@@ -0,0 +1,44 @@
+'use strict';
+constcommon=require('../common.js');
+const{ ReadableStream }=require('node:stream/web');
+
+constbench=common.createBenchmark(main,{
+n: [1e5],
+type: ['normal','bytes'],
+});
+
+asyncfunctionmain({ n, type }){
+leti=0;
+constsource=type==='bytes' ?
+{
+type: 'bytes',
+pull(controller){
+if(i++<n)controller.enqueue(newUint8Array(16));
+elsecontroller.close();
+},
+} :
+{
+pull(controller){
+if(i++<n)controller.enqueue('a');
+elsecontroller.close();
+},
+};
+
+constrs=newReadableStream(source);
+const[branch1,branch2]=rs.tee();
+constreader1=branch1.getReader();
+constreader2=branch2.getReader();
+letreads=0;
+
+bench.start();
+for(;;){
+const[result1,result2]=awaitPromise.all([
+reader1.read(),
+reader2.read(),
+]);
+if(result1.done||result2.done)break;
+reads++;
+}
+bench.end(reads);
+console.assert(reads===n);
+}