list_files vomits over the non-existence of 'none'. The definition of $used_theme is
authorebullient <ebullient@7612ce4b-ef26-0410-bec9-ea0150e637f0>
Fri, 6 Jul 2007 23:49:59 +0000 (23:49 +0000)
committerebullient <ebullient@7612ce4b-ef26-0410-bec9-ea0150e637f0>
Fri, 6 Jul 2007 23:49:59 +0000 (23:49 +0000)
commitcd81f9562ceed8c2fac4462c7f2055e6d9ca5c8c
tree90f6722ce650782d35ad1e7b755dcc7bc7034f3c
parenta14da8d673346da9d85bdb0ade10e246cf8baa1d
list_files vomits over the non-existence of 'none'. The definition of $used_theme is
arguably wrong, but either way, 'none' means 'none', and we shouldn't go off
listing files if that's the value.

git-svn-id: https://svn.code.sf.net/p/squirrelmail/code/trunk/squirrelmail@12507 7612ce4b-ef26-0410-bec9-ea0150e637f0
functions/page_header.php