MAC Cookies (patch 4 of N)

Wire up the pieces of MAC cookies (behind the --enable-mac-cookies flag).
Also, update the syntax of the header now that issuer has been removed and the
timestamp and nonce are combined into one field.

Review URL: http://codereview.chromium.org/6969050

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@85309 0039d316-1c4b-4281-b951-d872f2087c98
7 files changed