Print tools/perf/run_benchmark list on stdout instead of stderr

Print tools/perf/run_benchmark list on stdout instead of stderr

This patch changes tools/perf/run_benchmark to output the list command
on stdout instead of stderr. This makes grepping for benchmarks easier.

Note: The run command will still output the benchmark list on stderr if
an invalid benchmark is specified.

Committed: https://crrev.com/e2988849a05e193adb21091d0f89ba96dd1b65ac
Cr-Commit-Position: refs/heads/master@{#317712}

[alancutter (OOO until 2018), 2015-02-23 00:47:29]

alancutter@chromium.org changed reviewers:
+ dtu@chromium.org

[sullivan, 2015-02-23 14:53:10]

sullivan@chromium.org changed reviewers:
+ sullivan@chromium.org

[sullivan, 2015-02-23 14:53:11]

lgtm

[dtu, 2015-02-23 22:54:12]

lgtm

Also you can do fuzzy matching, e.g.: run_benchmark list smooth

[alancutter (OOO until 2018), 2015-02-23 23:47:38]

On 2015/02/23 22:54:12, dtu wrote:
> lgtm
> 
> Also you can do fuzzy matching, e.g.: run_benchmark list smooth

Didn't know this, thanks!

[alancutter (OOO until 2018), 2015-02-23 23:47:41]

The CQ bit was checked by alancutter@chromium.org

[commit-bot: I haz the power, 2015-02-23 23:52:24]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/948793002/1

[commit-bot: I haz the power, 2015-02-24 01:07:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-24 01:08:19]

Patchset 1 (id:??) landed as
https://crrev.com/e2988849a05e193adb21091d0f89ba96dd1b65ac
Cr-Commit-Position: refs/heads/master@{#317712}