Add support for command line switches to Features, and as proof that it works,

Add support for command line switches to Features, and as proof that it works,
use it for the experimental permission.

BUG=440194
R=rockot@chromium.org

Committed: https://crrev.com/ae342c9a0fa8a3c55bc89bf9a1543ad85f7d404f
Cr-Commit-Position: refs/heads/master@{#308176}

[not at google - send to devlin, 2014-12-12 01:35:27]

Patchset #3 (id:40001) has been deleted

[not at google - send to devlin, 2014-12-12 01:38:00]

Alright, here we go.

Now, this does actually change the behaviour of installing off-store Extensions
which request the "experimental" permission (without the flag on). Previously
the whole Extension would fail to install. Now it will install but show a
warning and ignore the permission.

I think this is the correct behaviour. Aside from that though, it doesn't matter
a whole lot since most Extension installations from the webstore anyway.

[Ken Rockot(use gerrit already), 2014-12-12 02:17:04]

lgtm

[Ken Rockot(use gerrit already), 2014-12-12 02:17:16]

On 2014/12/12 02:17:04, Ken Rockot wrote:
> lgtm

(barring what i assume are just merge conflict failures)

[not at google - send to devlin, 2014-12-12 17:49:29]

On 2014/12/12 02:17:16, Ken Rockot wrote:
> On 2014/12/12 02:17:04, Ken Rockot wrote:
> > lgtm
> 
> (barring what i assume are just merge conflict failures)

so weird, just rebased and didn't get any conflicts. huh.

[not at google - send to devlin, 2014-12-12 17:49:40]

The CQ bit was checked by kalman@chromium.org

[commit-bot: I haz the power, 2014-12-12 17:51:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/801603002/80001

[not at google - send to devlin, 2014-12-12 17:58:13]

The CQ bit was checked by kalman@chromium.org

[commit-bot: I haz the power, 2014-12-12 17:58:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/801603002/100001

[commit-bot: I haz the power, 2014-12-12 18:53:23]

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

[commit-bot: I haz the power, 2014-12-12 18:53:24]

Try jobs failed on following builders:
  linux_chromium_asan_rel on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  mac_chromium_rel_ng on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[not at google - send to devlin, 2014-12-12 20:25:58]

Well, this CL became more about making the experimental permission a warning
rather than an error. Oh well, should have picked a better guinea pig, it's just
the first thing that came to mind.

In any case, not *too* many changes, and this should go through.

[not at google - send to devlin, 2014-12-12 20:26:01]

The CQ bit was checked by kalman@chromium.org

[commit-bot: I haz the power, 2014-12-12 20:27:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/801603002/120001

[commit-bot: I haz the power, 2014-12-12 22:04:38]

Committed patchset #6 (id:120001)

[commit-bot: I haz the power, 2014-12-12 22:05:22]

Patchset 6 (id:??) landed as
https://crrev.com/ae342c9a0fa8a3c55bc89bf9a1543ad85f7d404f
Cr-Commit-Position: refs/heads/master@{#308176}