TinyMCE: update translatable strings, see #27453, #24067
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git-svn-id: http://core.svn.wordpress.org/trunk@27757 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Background Updates: Fix a PHP Warning caused by a Upgrader instance being passed into the Theme & Plugin $extra_stats parameter. See #27633

Built from https://develop.svn.wordpress.org/trunk@27928


git-svn-id: http://core.svn.wordpress.org/trunk@27758 1a063a9b-81f0-0310-95a4-ce76da25c4cd