Invalid markup in administration pages

[wahgnube]

I have attached a patch which fixes several small validation errors when rendering pages in wp-admin. There are a few more fixes to follow to get all the current core trunk admin pages to render without validation errors.

(In [16817]) Close br. Props wahgnube. see #15287

Exisitng patch has issues with each piece. I don't know why some things are changing. We can't pass amp; into wp_redirect. Some appear invalid. Some not.

No patch, low priority, punting.

Would like new eyes on the wp-admin/includes/template.php change. Are we seeing any issues there with JS or such? Let's fix it if there's an issue.

In the case of the wp-admin/edit-comments.php diff, the </div> is for div#wrap and needs to be moved outside of the form, rather than the form moved inside the div.

In the case of the wp-admin/upload.php diff, the </div> should be removed; it is the same issue -- closing div#wrap too early, which is closed later again. If I had to guess, the floating clear is necessary inside the </form>, but the one outside can be removed.

The wp-admin/edit-tags.php diff can be ignored. I can't find $location used for anything beyond redirects, which should not have amp encoding. (As it's a global, some other function might be pulling it in. Leaving it alone.)

In the case of the wp-admin/includes/template.php diff, the ID addmetasub is used only for styling. The addmeta name is, importantly, used in the post handler. This change would break the form. I do not know what this is trying to fix.

Untested; diff is final for the ticket and just based on studying the code. Need to run validation passes, sanity checks, and confirm that the UI didn't explode.

15287.2..patch with some more validation error fixes.

Looks fine. Not a fan of the md5, but it works.

(In [17129]) Validation fixes. props ocean90, fixes #15287.