GN: Re-enable platform unit test targets

GN: Re-enable platform unit test targets

On linux use_webaudio_ffmpeg is true and when it is platform needs to
depend on //third_party/ffmpeg. This target is set up in the GN build now
(at least for this platform), so it's safe to re-enable.

R=brettw@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=177142

[jamesr, 2014-06-26 05:41:58]

Finally got a chance to look into this - didn't manage to land the ffmpeg dep
last time (which isn't needed on mac).  Not sure why trybots didn't catch it,
guess they didn't run GN?

[brettw, 2014-06-26 05:46:38]

lgtm

[jamesr, 2014-06-26 06:01:18]

The CQ bit was checked by jamesr@chromium.org

[commit-bot: I haz the power, 2014-06-26 06:01:38]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jamesr@chromium.org/353943003/1

[commit-bot: I haz the power, 2014-06-26 06:45:02]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  mac_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/mac_blink_rel/builds/12865)

[abarth-chromium, 2014-06-26 06:54:06]

On 2014/06/26 at 05:41:58, jamesr wrote:
> Not sure why trybots didn't catch it, guess they didn't run GN?

They run GN release.  The issue apparently only manifests in GN debug.

[jamesr, 2014-06-26 06:55:55]

On 2014/06/26 06:54:06, abarth wrote:
> On 2014/06/26 at 05:41:58, jamesr wrote:
> > Not sure why trybots didn't catch it, guess they didn't run GN?
> 
> They run GN release.  The issue apparently only manifests in GN debug.

It failed in release for me locally.¯\(°_o)/¯

[commit-bot: I haz the power, 2014-06-27 12:45:59]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-06-27 12:46:00]

Exceeded time limit waiting for builds to trigger.

[jamesr, 2014-06-27 21:22:55]

The CQ bit was checked by jamesr@chromium.org

[commit-bot: I haz the power, 2014-06-27 21:24:00]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jamesr@chromium.org/353943003/1

[commit-bot: I haz the power, 2014-06-27 21:41:27]

Change committed as 177142