Customize: Ensure customization drafts are published instead of trashed when...

Customize: Ensure customization drafts are published instead of trashed when scheduled changeset goes live while non-admin user is authenticated (such as during WP Cron).

Props designsimply for testing, dlh for testing, melchoyce for testing.
See #28721, #34923, #42220.
Fixes #42489 for trunk.

Built from https://develop.svn.wordpress.org/trunk@42148


git-svn-id: https://core.svn.wordpress.org/trunk@41979 1a063a9b-81f0-0310-95a4-ce76da25c4cd