autotest: perf upload higher_is_better defaults to None.

It was noted that ChromeOS telemetry always uploads with
higher_is_better=True. This prevents it from being processed
as on other platforms. Most pure autotests are already setting
this value. And the dashboard seems to still handle None
perfectly fine.

TEST=None.
BUG=chromium:431990

Change-Id: I4a3eae7686d98da5647d338aca6dd3fa8187f4b9
Reviewed-on: https://chromium-review.googlesource.com/228374
Tested-by: Ilja Friedel <ihf@chromium.org>
Reviewed-by: Fang Deng <fdeng@chromium.org>
Reviewed-by: Quinten Yearsley <qyearsley@chromium.org>
Commit-Queue: Ilja Friedel <ihf@chromium.org>
1 file changed