Remove substrate-in-the-browser (#9541)

* Comment out browser stuff

* Remove browser stuff

* Remove more wasm transport code

* Remove ExtTransport and rework how telemetry initialises.

* Change (most) wasm-timer using code to use std::time

* Rename CI-job

* Aura does not compile for wasm

* Remove testing in the browser on CI

* Update README

* Leave `StreamSink` be

* fmt

substrate/client/network/src/transport.rs

@@ -25,7 +25,7 @@ use libp2p::{
 		transport::{Boxed, OptionalTransport},
 		upgrade,
 	},
-	identity, mplex, noise, wasm_ext, PeerId, Transport,
+	identity, mplex, noise, PeerId, Transport,
 };
 #[cfg(not(target_os = "unknown"))]
 use libp2p::{dns, tcp, websocket};
@@ -51,18 +51,11 @@ pub use self::bandwidth::BandwidthSinks;
 pub fn build_transport(
 	keypair: identity::Keypair,
 	memory_only: bool,
-	wasm_external_transport: Option<wasm_ext::ExtTransport>,
 	yamux_window_size: Option<u32>,
 	yamux_maximum_buffer_size: usize,
 ) -> (Boxed<(PeerId, StreamMuxerBox)>, Arc<BandwidthSinks>) {
 	// Build the base layer of the transport.
-	let transport = if let Some(t) = wasm_external_transport {
-		OptionalTransport::some(t)
-	} else {
-		OptionalTransport::none()
-	};
-	#[cfg(not(target_os = "unknown"))]
-	let transport = transport.or_transport(if !memory_only {
+	let transport = if !memory_only {
 		let desktop_trans = tcp::TcpConfig::new().nodelay(true);
 		let desktop_trans =
 			websocket::WsConfig::new(desktop_trans.clone()).or_transport(desktop_trans);
@@ -73,9 +66,9 @@ pub fn build_transport(
 			EitherTransport::Right(desktop_trans.map_err(dns::DnsErr::Transport))
 		})
 	} else {
+		// For the in-memory case we set up the transport with an `.or_transport` below.
 		OptionalTransport::none()
-	});
-
+	};
 	let transport = transport.or_transport(if memory_only {
 		OptionalTransport::some(libp2p::core::transport::MemoryTransport::default())
 	} else {