Change dont_embed_build_metadata default to 1 except for Official build.

Change dont_embed_build_metadata default to 1 except for Official build.

It's time to start reaping the benefits. Right now only base_unittests and
net_unittests on linux will benefit from it but it'll soon increase in coverage.
Setting it as the default removes the issues where a build would fail locally
but pass on the TS (or the reverse). The option is still there in case someone
really desire to embed timestamps in their build.

R=sebmarchand@chromium.org
BUG=314403

[Sébastien Marchand, 2014-10-30 01:44:40]

Not sure that it's safe to do this for the official builds... The function
GetBuildTime has been patched but some part of Chrome still depend on it e.g.
https://code.google.com/p/chromium/codesearch#chromium/src/base/metrics/field...

Maybe this should be set to 1 by default just for the non-official builds ?

[M-A Ruel, 2014-10-30 13:29:09]

On 2014/10/30 01:44:40, Sébastien Marchand wrote:
> Not sure that it's safe to do this for the official builds... The function
> GetBuildTime has been patched but some part of Chrome still depend on it e.g.
>
https://code.google.com/p/chromium/codesearch#chromium/src/base/metrics/field...
> 
> Maybe this should be set to 1 by default just for the non-official builds ?

Done, tested with:

rm -rf out/Debug
gclient runhooks
grep -R DONT_EMBED_BUILD_METADATA out/Debug
(find lots of defines)
export GYP_DEFINES="buildtype=Official ..."
gclient runhooks
grep -R DONT_EMBED_BUILD_METADATA out/Debug
(finds nothing)

[Sébastien Marchand, 2014-10-30 14:19:01]

The CQ bit was checked by sebmarchand@chromium.org

[Sébastien Marchand, 2014-10-30 14:19:01]

lgtm

[commit-bot: I haz the power, 2014-10-30 14:19:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/685123005/20001

[commit-bot: I haz the power, 2014-10-30 15:13:07]

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

[commit-bot: I haz the power, 2014-10-30 15:13:08]

Try jobs failed on following builders:
  ios_dbg_simulator on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/ios_dbg_simulator...)

[M-A Ruel, 2014-10-30 15:14:59]

The CQ bit was checked by maruel@chromium.org

[commit-bot: I haz the power, 2014-10-30 15:15:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/685123005/20001

[M-A Ruel, 2014-10-30 15:17:39]

The CQ bit was unchecked by maruel@chromium.org

[Sébastien Marchand, 2014-10-30 15:20:06]

The trybot failed for valid reasons... There's some test requiring  a valid
build time :(, like this one:
https://code.google.com/p/chromium/codesearch#chromium/src/base/metrics/field...

GetLastYear() is passed as an expiration date to FactoryGetFieldTrial(...), so
in theory this test is flaky... If you run it one year after building it then
the result is different from when you run it just after building it...