Issue #1816136 by Berdir, David_Rothstein, ubercomp, c960657, wojtha, fgm,...

Issue #1816136 by Berdir, David_Rothstein, ubercomp, c960657, wojtha, fgm, pwolanin, Damien Tournoud, Heine: Fixed OpenID vulnerability from SA-CORE-2012-003 (and backport anything to 7.x-dev as necessary).