toolchain-utils: update email sending for nightly test

This patch provides follow up to http://crrev.com/c/2119231.

Crosperf will return non-zero when terminated or at least one test
failed. When tests partially succeed, reports will still be generated,
otherwise no reports.

We will try to access the report no matter Crosperf's return value,
send email and copy json report to archive dir; and then raise error
when Crosperf returns non-zero accordingly.

Also add date to the email title.

BUG=chromium:1063703
TEST=Simply tested the coverage with print.

Change-Id: I4b3f3667cf3a0fd9cef4906052de38432684862c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/2137941
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Commit-Queue: Zhizhou Yang <zhizhouy@google.com>
Tested-by: Zhizhou Yang <zhizhouy@google.com>
Auto-Submit: Zhizhou Yang <zhizhouy@google.com>
1 file changed