Default value for $credentials parameter in wp_signon() should be an array, not a string.

props tivnet.
fixes #27130.
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git-svn-id: http://core.svn.wordpress.org/trunk@27201 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Remove redundant add_filter() call. see [24848]. fixes #27255.
Built from https://develop.svn.wordpress.org/trunk@27351


git-svn-id: http://core.svn.wordpress.org/trunk@27202 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Remove extra comma. props jorbin. see #19845.
Built from https://develop.svn.wordpress.org/trunk@27352


git-svn-id: http://core.svn.wordpress.org/trunk@27203 1a063a9b-81f0-0310-95a4-ce76da25c4cd