Run media_perftests in a single process.

Run media_perftests in a single process.

Running performance tests in multiple processes doesn't really make sense if we want consistent numbers, and this also fixes performance reporting to the dashboard.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=243214

[rileya (GONE FROM CHROMIUM), 2014-01-06 23:37:28]

The switch to the new test runner by default seems to have broken
media_perftests' perf reporting. Its performance numbers are printed to stdout,
but when run over multiple processes in the new runner we don't seem to get
stdout from the tests.

I added the single process flag to fix this. In the interest of consistent
numbers I don't think we don't want multiple processes for performance tests
anyways.

[ghost stip (do not use), 2014-01-06 23:41:36]

lgtm, this seems reasonable.

Paweł and Tony, are there other perf tests where we would need to do this? IIRC
most of them are on telemetry by now.

[tonyg, 2014-01-06 23:44:32]

On 2014/01/06 23:41:36, stip wrote:
> lgtm, this seems reasonable.

lgtm2

> Paweł and Tony, are there other perf tests where we would need to do this?
IIRC
> most of them are on telemetry by now.

We should probably do this for all perf tests that aren't on telemetry
(cc_perftests, performance_ui_tests, etc).

[commit-bot: I haz the power, 2014-01-07 00:55:29]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rileya@chromium.org/112633009/1

[commit-bot: I haz the power, 2014-01-07 00:56:28]

Change committed as 243214

[Paweł Hajdan Jr., 2014-01-08 16:52:37]

Sorry, I don't think this is correct.

Please see https://codereview.chromium.org/128643002/ and
https://codereview.chromium.org/128593002 where I apply a different approach.