Updated the generated policy documentation.

This update removes references to the Windows registry, and adds a note that
since Chrome 28 the registry isn't used anymore.

BUG=259236

Review URL: https://chromiumcodereview.appspot.com/19181002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@211645 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed