Reland "Fix fake audio setup in WebRTC audio perf tests."

This is a reland of c0d567278fa84771b439b83b7fbd5421107b84c5

The fix helps only on Mac and Linux.

Original change's description:
> Fix fake audio setup in WebRTC audio perf tests.
>
> Change them to set up switches::kUseFileForFakeAudioCapture in
> SetUpCommandLine(), so that it can be propagated to the audio process.
>
> Bug: 850936
> Change-Id: Ia6cccc01d2b5fa7545abe8cb1554d72c33146566
> Reviewed-on: https://chromium-review.googlesource.com/1122857
> Reviewed-by: Henrik Boström <hbos@chromium.org>
> Commit-Queue: Olga Sharonova <olka@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#572142}

Bug: 850936
Change-Id: Ida4f3b888bc0332b68050d6b1cb8a0d5fef3cf32
Reviewed-on: https://chromium-review.googlesource.com/1124519
Reviewed-by: Henrik Boström <hbos@chromium.org>
Commit-Queue: Henrik Boström <hbos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572189}
1 file changed