GCS: keep browser buttons working regardless of state

This is a workaround for the fact the modem doens't trigger
a correctly opened state. It also doesn't even start handshaking
by itself, so the session management never even fails.

In general it's useful to keep the browser buttons working for
debugging purposes even if a valid session hasn't been established.
The change would make more sense if done on line 509. I can make some code to make session managing a GCS option, it will probably be useful for other situations in the future.