chore(agnostification): create web for web only code

[jackfranklin]

This change makes a web folder to house any code that is just for the
browser and won't work in a Node environment.

We have three folders now to divide code up nicely:

• node
• web
• common.

[jackfranklin]

One thing I'd welcome opinions on: the two WebSocketTransport classes are almost identical bar the slight difference in how we create the socket (Node's ws lib vs browser) and in the types (one has private ws: NodeWebSocket and the other private ws: WebSocket).

That said, I cannot find a nice way to avoid the duplication in the code that doesn't 1) make it far more complex, 2) lose some type safety. That's why I've left the duplication as I think it's actually best (or least worst) compared to forcing an abstraction.

[mathiasbynens]

How did you arrive at web and not browser? The latter seems more precise but I might be missing some context.

[jackfranklin]

How did you arrive at web and not browser? The latter seems more precise but I might be missing some context.

None really beyond I think we've talked about it as puppeteer-web and I named the entrypoint web.js. I don't have a strong feeling either way on which we should go but we should be consistent.

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[jschfflr]

@googlebot I consent.

[jschfflr]

@jackfranklin I updated the pr - let me know if you think it's still relevant.
There's one change in the Node WebSocket that I'm not sure we can also include in the web version:

puppeteer/src/node/NodeWebSocketTransport.ts

Line 29 in cb4470a

'User-Agent': `Puppeteer ${pkg.version}`,

Do you know if that would be possible?

[jschfflr]

Closing this for now as discussed offline with @jackfranklin