google: prefer os.Getenv("HOME") over os/user.Current() so as to avoid SEGV
google: prefer os.Getenv("HOME") over os/user.Current() so as to avoid SEGV

Due to an issue in handling thread-local storages, os/user can lead to SEGV
when glibc is statically linked with.

So we prefer os.Getenv("HOME") for guessing where is the home directory.

See also: golang/go#13470

Change-Id: I1046ff93a71aa3b11299f7e6cf65ff7b1fb07eb9
Reviewed-on: https://go-review.googlesource.com/34175
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

golang/oauth2