Type cast `$nonce` to string in `wp_verify_nonce()`.

props jesin.
fixes #29542.

git-svn-id: https://develop.svn.wordpress.org/trunk@30576 602fd350-edb4-49c9-b593-d223f7449a82
Remove the `wp_is_trusted_network()` function pending further discussion on terminology and behaviour.

See #30145


git-svn-id: https://develop.svn.wordpress.org/trunk@30577 602fd350-edb4-49c9-b593-d223f7449a82
Network Admin: Improve width of input fields on Add New Site and Edit Site screens.

props honeysilvas.
fixes #16383.

git-svn-id: https://develop.svn.wordpress.org/trunk@30578 602fd350-edb4-49c9-b593-d223f7449a82
Comments: Use proper HTTP response codes for validation errors.

props miqrogroove, solarissmoke, mackensen.
fixes #11286.

git-svn-id: https://develop.svn.wordpress.org/trunk@30579 602fd350-edb4-49c9-b593-d223f7449a82