Fix content membership validation failing when content id is in use on another content type with the same ID.
Fix content membership validation failing when content id is in use on another content type with the same ID.

elcom/gitorious,SamuelMoraesF/Gitorious,tigefa4u/gitorious-mainline,tigefa4u/gitorious-mainline,gitorious/mainline,elcom/gitorious,rae/gitorious-mainline,spencerwp/mainline,SamuelMoraesF/Gitorious,rae/gitorious-mainline,gitorious/mainline,Gitorious-backup/mainline,Gitorious-backup/mainline,rae/gitorious-mainline,spencerwp/mainline,elcom/gitorious,SamuelMoraesF/Gitorious,gitorious/mainline,Gitorious-backup/mainline,rae/gitorious-mainline,tigefa4u/gitorious-mainline,SamuelMoraesF/Gitorious,spencerwp/mainline,Gitorious-backup/mainline,spencerwp/mainline,gitorious/mainline,tigefa4u/gitorious-mainline,elcom/gitorious