Consider using native StringEncoder when available

[feross]

There's a native html5 api for string encoding and decoding. Benchmark it and see if it's faster to use it, when possible.

[mourner]

Tried that here — nope. Extremely harmful for performance — with native TextEncoder/TextDecoder, it's like 5x slower in Chrome.

[feross]

Good to know. The API will probably get faster in a few years when the API is used more in the wild and there's a reason to optimize it.

I'll close this issue for now, since we can't afford a 5x perf hit.