Add "sidebar" section to extension manifest:

  "sidebar": {
    "default_url": "",
    "default_title": "",
    "default_icon": ""
  }

Allow extension to access experimental.sidebar API only in presence of this section.

BUG=51084
TEST=unit_tests, ExtensionManifestTest.Sidebar

Review URL: http://codereview.chromium.org/6321006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@71993 0039d316-1c4b-4281-b951-d872f2087c98
27 files changed