[autotest] Teach suite.py to send emails when do not file bug

In the future, we will send emails for the failures of some suites
rather than auto-filing bugs.

BUG=chromium:526287
TEST=Test with unittest and fake dummy suite with file_bug=True and
owner is myself. When test fails, received expected email sent to me.

Change-Id: Ied43fbcfd1d46b09951a8170635d88f10878b46d
Reviewed-on: https://chromium-review.googlesource.com/296402
Commit-Ready: Shuqian Zhao <shuqianz@chromium.org>
Tested-by: Shuqian Zhao <shuqianz@chromium.org>
Reviewed-by: Fang Deng <fdeng@chromium.org>
2 files changed