Jeremy Felt 1ffba4abc4 Differentiate between invalid and missing admin emails when adding a new site
Check the emptiness of the admin email before using `sanitize_email()` and `is_email()` to determine if the address is valid.

Fixes #17890

Built from https://develop.svn.wordpress.org/trunk@29877


git-svn-id: http://core.svn.wordpress.org/trunk@29634 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2014-10-12 00:22:18 +00:00
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2014-10-02 15:49:17 +00:00