Themes: When the user doesn't have switch_themes capabilities, and we've passed the current theme, detect the theme slug/stylesheet correctly so that the flags are set properly. See #25948

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git-svn-id: http://core.svn.wordpress.org/trunk@26367 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Themes: Do extra Cap checks before outputting links, and use full URI's. See #25948

Built from https://develop.svn.wordpress.org/trunk@26470


git-svn-id: http://core.svn.wordpress.org/trunk@26368 1a063a9b-81f0-0310-95a4-ce76da25c4cd