x/net/websocket: websocket connections through HTTP proxies not supported

[gopherbot]

by aaron@hubernet.net:

What steps will reproduce the problem?
If possible, include a link to a program on play.golang.org.
1.  Use the websocket client to initiate a connection where an HTTP proxy is required.

What is the expected output?
Successful HTTP CONNECT is issued via the proxy server to the endpoint.

What do you see instead?
Connection is attempted directly and fails.

Current websocket code does not contain any logic to connect via an HTTP proxy server
which is supported by the WebSockets protocol.

[rsc]

Comment 1:

Labels changed: added repo-net.