Fix appViewGuestInternal error in background pages.

Fix appViewGuestInternal error in background pages.

Make appViewGuestInternal available in all channels, note that this
doesn't expose <appview> to all channels, appViewEmbedderInternal
controls that.
Making appViewGuestInternal available in all channel would make
require('binding').Binding.create('appViewGuestInternal').generate();
from app_runtime_custom_bindings.js not complain.

BUG=437891
Test=Note that this fix is only going to show up in stable/beta.
1) Get unpacked calculator app from here:
https://github.com/GoogleChrome/chrome-app-samples/tree/master/samples/calculator
2) This app has background page.
Open the app in chrome stable or beta.
3) Right click and select "Inspect background page".
The following error in background page's console should not
show up.
"chrome.appViewInternal is not available: 'appViewInternal' requires Google Chrome dev channel or newer, but this is the stable channel."

Committed: https://crrev.com/26e03835341edc959c4d69c1c01346c1f3cec99d
Cr-Commit-Position: refs/heads/master@{#306310}

[lazyboy, 2014-12-01 20:58:49]

lazyboy@chromium.org changed reviewers:
+ fsamuel@chromium.org

[Fady Samuel, 2014-12-01 21:00:26]

lgtm

[lazyboy, 2014-12-01 21:19:05]

lazyboy@chromium.org changed reviewers:
+ kalman@chromium.org

[lazyboy, 2014-12-01 21:19:06]

+kalman for reviewing.

[not at google - send to devlin, 2014-12-01 23:28:34]

lgtm

https://chromiumcodereview.appspot.com/773583003/diff/1/extensions/common/api...
File extensions/common/api/_api_features.json (right):

https://chromiumcodereview.appspot.com/773583003/diff/1/extensions/common/api...
extensions/common/api/_api_features.json:81: // appViewEmbedderInternal is
required for that.
Reference the bug as to why you need it.

[lazyboy, 2014-12-01 23:57:55]

https://chromiumcodereview.appspot.com/773583003/diff/1/extensions/common/api...
File extensions/common/api/_api_features.json (right):

https://chromiumcodereview.appspot.com/773583003/diff/1/extensions/common/api...
extensions/common/api/_api_features.json:81: // appViewEmbedderInternal is
required for that.
On 2014/12/01 23:28:34, kalman wrote:
> Reference the bug as to why you need it.

Done.

[lazyboy, 2014-12-02 00:05:46]

The CQ bit was checked by lazyboy@chromium.org

[commit-bot: I haz the power, 2014-12-02 00:07:22]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/773583003/20001

[commit-bot: I haz the power, 2014-12-02 01:10:11]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2014-12-02 01:10:55]

Patchset 2 (id:??) landed as
https://crrev.com/26e03835341edc959c4d69c1c01346c1f3cec99d
Cr-Commit-Position: refs/heads/master@{#306310}