Similar to GC::Root<T>, make GC::RootVector<T> constructible without
explicitly passing a Heap.
This is implemented by having RootVectorBase use GC::Heap::the() for
heap-free construction.
Teach readable byte stream enqueueing about native byte producers by
sharing the post-transfer part of the spec algorithm. This lets fetch
hand owned network bytes directly to the byte stream controller instead
of first wrapping them in an unobservable Uint8Array and then
transferring its buffer back into another ArrayBuffer.
Keep the public enqueue(chunk) path spec-shaped and make the native
path rejoin after the TransferArrayBuffer step, so observable chunks are
still created by the shared reader and queue handling code.
This reduces GC churn while playing YouTube videos.
The main streams AO file has gotten very large, and is a bit difficult
to navigate. In an effort to improve DX, this migrates WritableStream
AOs to their own file.
The main streams AO file has gotten very large, and is a bit difficult
to navigate. In an effort to improve DX, this migrates ReadableStream
AOs to their own file. And the helper classes used for the tee and pipe-
to operations are also in their own files.
