Move declarative api files to extensions/browser/api/declarative.

Move declarative api files to extensions/browser/api/declarative.

This cl also includes some small changes to remove
chrome/extensions dependencies in these files, e.g.
it gets IsIncognitoEnabled() from ExtensionPrefs()
instead of util::IsIncognitoEnabled().

BUG=352293
Committed: https://crrev.com/97b60ee352ca47814774ffe9a4bebfc6d44b3e05
Cr-Commit-Position: refs/heads/master@{#294186}

[wjmaclean, 2014-09-09 22:12:35]

Patchset #7 (id:120001) has been deleted

[wjmaclean, 2014-09-09 22:12:50]

Patchset #6 (id:100001) has been deleted

[wjmaclean, 2014-09-10 14:22:03]

wjmaclean@chromium.org changed reviewers:
+ rockot@chromium.org

[wjmaclean, 2014-09-10 14:23:03]

rockot@ - I think this is ready (or at least very close). Would you mind taking
a look?

[Ken Rockot(use gerrit already), 2014-09-10 16:30:32]

I've got nothing to add, lgtm!

[wjmaclean, 2014-09-10 16:33:06]

The CQ bit was checked by wjmaclean@chromium.org

[commit-bot: I haz the power, 2014-09-10 16:34:05]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/wjmaclean@chromium.org/550403003/170046

[commit-bot: I haz the power, 2014-09-10 17:22:38]

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

[commit-bot: I haz the power, 2014-09-10 17:22:39]

Try jobs failed on following builders:
  android_aosp on tryserver.chromium.linux (None)

[wjmaclean, 2014-09-10 17:28:44]

The CQ bit was checked by wjmaclean@chromium.org

[commit-bot: I haz the power, 2014-09-10 17:30:15]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/wjmaclean@chromium.org/550403003/170046

[commit-bot: I haz the power, 2014-09-10 17:33:36]

Committed patchset #9 (id:170046) as 757077deb9e438fc3ba401a991053df2a21c8f6a

[commit-bot: I haz the power, 2014-09-10 17:42:07]

Patchset 9 (id:??) landed as
https://crrev.com/97b60ee352ca47814774ffe9a4bebfc6d44b3e05
Cr-Commit-Position: refs/heads/master@{#294186}