Fix ws tests.

devtools/src/http_client.rs

@@ -16,7 +16,7 @@
 
 use std::thread;
 use std::time::Duration;
-use std::io::{Read, Write};
+use std::io::{self, Read, Write};
 use std::str::{self, Lines};
 use std::net::{TcpStream, SocketAddr};
 
@@ -87,6 +87,7 @@ pub fn request(address: &SocketAddr, request: &str) -> Response {
 	loop {
 		let mut chunk = [0; 32 *1024];
 		match req.read(&mut chunk) {
+			Err(ref err) if err.kind() == io::ErrorKind::WouldBlock => break,
 			Err(err) => panic!("Unable to read response: {:?}", err),
 			Ok(0) => break,
 			Ok(read) => response.extend_from_slice(&chunk[..read]),