Revert of Disable smoothness.top_25_smooth on win/mac/linux. (patchset #1 id:1 of https://codereview.chromium.org/1238073003/)
Revert of Disable smoothness.top_25_smooth on win/mac/linux. (patchset #1 id:1 of https://codereview.chromium.org/1238073003/)

Reason for revert:
This was caused by https://codereview.chromium.org/1234223003, which has been reverted.

BUG=510818

Original issue's description:
> Disable smoothness.top_25_smooth on win/mac/linux.
>
> BUG=510818
>
> Committed: https://crrev.com/d143ef088ec1069825eb9a585d82be3b4ccc9ce6
> Cr-Commit-Position: refs/heads/master@{#339041}

TBR=sullivan@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=510818

Review URL: https://codereview.chromium.org/1245483002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#339259}

lihui7115/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,lihui7115/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend,lihui7115/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend,lihui7115/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,lihui7115/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend,lihui7115/ChromiumGStreamerBackend,lihui7115/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend,lihui7115/ChromiumGStreamerBackend,lihui7115/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,ltilve/ChromiumGStreamerBackend,CapOM/ChromiumGStreamerBackend