syscall: TestLinuxDeathSignal fails on brillo

[rakyll]

Reproducible on Qualcomm Dragonboard 410c, Brillo image built with BDK 7.5.4.

go_android_exec: adb shell mkdir -p /mnt/media_rw/tmp/syscall.test-55724
go_android_exec: adb push /var/folders/00/1b8h8000h01000cxqpysvccm005d21/T/go-build559449628/syscall/_test/syscall.test /mnt/media_rw/tmp/syscall.test-55724/syscall.test-55724-tmp
2842 KB/s (3472036 bytes in 1.192s)
go_android_exec: adb shell cp '/mnt/media_rw/tmp/syscall.test-55724/syscall.test-55724-tmp' '/mnt/media_rw/tmp/syscall.test-55724/syscall.test-55724'
go_android_exec: adb shell rm '/mnt/media_rw/tmp/syscall.test-55724/syscall.test-55724-tmp'
go_android_exec: adb shell export TMPDIR="/mnt/media_rw/tmp/syscall.test-55724"; export GOROOT="/mnt/media_rw/goroot/"; export GOPATH="/mnt/media_rw/gopath/"; cd "/mnt/media_rw/goroot/src/syscall"; '/mnt/media_rw/tmp/syscall.test-55724/syscall.test-55724' -test.short=true -test.timeout=6m0s; echo -n exitcode=$?
death signal parent error: fork/exec /mnt/media_rw/tmp/syscall.test-55724/TestDeathSignal002741875/syscall.test-55724: permission denied
--- FAIL: TestLinuxDeathSignal (0.12s)
    syscall_linux_test.go:98: did not receive start from child, received "", EOF
FAIL
exitcode=1go_android_exec: adb shell rm -rf /mnt/media_rw/tmp/syscall.test-55724
FAIL    syscall 2.616s

[hyangah]

brillo is like android but not android.
Is there a light-weight way to check if we are on brillo even though GOOS=android?

[rakyll]

I have been told that /etc/os-release.d/bdk_version file is what we should look for. There is no other better canonical way for now. And since Brillo images could be significantly altered by the users, stat'ing the BDK file seems like a reliable solution.