Move owned ArrayBuffer storage directly when transferring stream
buffers instead of copying the bytes before detaching the source.
WebAssembly memory continues to copy because its ArrayBuffer wraps
externally-owned storage.
Preserve the abrupt completion from DetachArrayBuffer before moving
storage so non-transferable buffers, such as WebAssembly.Memory-backed
views, still surface TypeError through stream operations instead of
aborting.
This saves ~130ms of main thread time when loading a YouTube video
on my Linux computer. :^)
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