Use current_user_can('manage_network_plugins') in validate_active_plugins() instead of is_super_admin().

props jdgrimes.
fixes #26068.

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git-svn-id: http://core.svn.wordpress.org/trunk@26480 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fourteen: fix JS lint errors in customizer.js file, see r26573.
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git-svn-id: http://core.svn.wordpress.org/trunk@26481 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Ensure that theme customizer buttons don't overlap on small screens; allow small-screen theme popup to use the full height of the viewport since the adminmenu is no longer fixed; ensure that buttons in the theme customizer wrap as efficiently as they can on mobile. Fixes #26361, props mattheu, iammattthomas.
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git-svn-id: http://core.svn.wordpress.org/trunk@26482 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Set Available and Inactive Widget areas to not collapse, since they don't look like collapsing elements. Fixes #26327, props MikeHansenMe.


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git-svn-id: http://core.svn.wordpress.org/trunk@26483 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Rename the new custom-background arguments passed to add_theme_support().

 * background-position becomes default-position-x
 * background-attachment becomes default-attachment
 * background-repeat becomes default-repeat

These are in line with existing default-image and default-color arguments, and also makes the position argument unambiguous and forwards compatible.

fixes #20816.

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git-svn-id: http://core.svn.wordpress.org/trunk@26484 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add .ab-empty-item to the responsive adminbar sizing adjustments. Ensure that hidden text in responsive adminbar stays properly hidden in Firefox. See #26299.


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git-svn-id: http://core.svn.wordpress.org/trunk@26485 1a063a9b-81f0-0310-95a4-ce76da25c4cd