Add shortcuts with a MAC

Intentionally breaks old webapp shortcuts to change the package prefixes
in the Intent extras.

BUG=285924
R=dtrainor@chromium.org, palmer@chromium.org

Review URL: https://codereview.chromium.org/24318004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225290 0039d316-1c4b-4281-b951-d872f2087c98