GitLab

This code is not chrome_elf-specific, rather, chrome_elf
is the only current user of it. Move the manifest building
logic to a more generic location.

BUG=324863

Review URL: https://codereview.chromium.org/137373002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245307 0039d316-1c4b-4281-b951-d872f2087c98