Introduce function preManifestDomInit_

Introduce function preManifestDomInit_ and move some DOM that do not depend on manifest initialization to it


BUG=314675

Review URL: https://codereview.chromium.org/67813010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236003 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236003