adb kindly doesn't forward exit codes until N (https://code.google.com/p/android/issues/detail?id=3254), so we need to work around it. Otherwise all our test failures have been silently ignored (oops!). Change-Id: I03440db7dd77e6b9af5445b309b67dc719cea054 Reviewed-on: https://boringssl-review.googlesource.com/8190 Reviewed-by: David Benjamin <davidben@google.com>