Ignore user ID post data. Merges [25316] to 3.6.


git-svn-id: https://develop.svn.wordpress.org/branches/3.6@25321 602fd350-edb4-49c9-b593-d223f7449a82
Tighten allowed upload file types. Merges [25317] to 3.6.


git-svn-id: https://develop.svn.wordpress.org/branches/3.6@25322 602fd350-edb4-49c9-b593-d223f7449a82
Validate referrers to prevent off-domain redirects. Merges [25318] to 3.6.


git-svn-id: https://develop.svn.wordpress.org/branches/3.6@25323 602fd350-edb4-49c9-b593-d223f7449a82
Better protocol validation in set_url_scheme(). Merges [25319] to 3.6.


git-svn-id: https://develop.svn.wordpress.org/branches/3.6@25324 602fd350-edb4-49c9-b593-d223f7449a82
Loose validation for is_serialized() in maybe_serialize(). Merges [25320] to 3.6.


git-svn-id: https://develop.svn.wordpress.org/branches/3.6@25325 602fd350-edb4-49c9-b593-d223f7449a82
3.6.1-RC1


git-svn-id: https://develop.svn.wordpress.org/branches/3.6@25326 602fd350-edb4-49c9-b593-d223f7449a82