components: Add BUILD.gn file to metrics so we can build it with GN.

components: Add BUILD.gn file to metrics so we can build it with GN.

Debug:

$ gn gen out/Debug_gn --args=is_debug=true
$ ninja -C out/Debug_gn metrics

Release:

$ gn gen out/Release_gn --args=is_debug=false
$ ninja -C out/Release_gn metrics

BUG=None
TEST=see above.
R=brettw@chromium.org
TBR=asvitkine@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=266675

[tfarina, 2014-04-24 01:09:40]

Brett -> review.

Alexei -> fyi.

[Alexei Svitkine (slow), 2014-04-24 02:28:49]

On 2014/04/24 01:09:40, tfarina wrote:
> Brett -> review.
> 
> Alexei -> fyi.

You might want to wait till https://codereview.chromium.org/239093004/ lands.

[tfarina, 2014-04-24 02:41:33]

On 2014/04/24 02:28:49, Alexei Svitkine wrote:
> On 2014/04/24 01:09:40, tfarina wrote:
> > Brett -> review.
> > 
> > Alexei -> fyi.
> 
> You might want to wait till https://codereview.chromium.org/239093004/ lands.

Not really. We don't have proto support yet, afaik. So the proto stuff that this
CL is adding can be added later.

[brettw, 2014-04-24 19:29:25]

lgtm

[tfarina, 2014-04-28 22:31:23]

Committed patchset #1 manually as r266675 (presubmit successful).