os/signal: disable loading of history during test

Bring in https://golang.org/cl/98616 from gc tip.

Original CL description:

    This change modifies Go to disable loading of users' shell history for
    TestTerminalSignal tests. TestTerminalSignal, as part of its workload,
    will execute a new interactive bash shell. Bash will attempt to load the
    user's history from the file pointed to by the HISTFILE environment
    variable. For users with large histories that may take up to several
    seconds, pushing the whole test past the 5 second timeout and causing
    it to fail.

Change-Id: Ifaf7ece4bded229c83f1ef0a289fb8418b3c01e2
Reviewed-on: https://go-review.googlesource.com/107624
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
1 file changed