Widgets:
- Fix support for expanding (wide) widgets in the Inactive Widgets area.
- Remove resizing of the sidebars height.
- Stop removing unneeded "for" attributes from labels inside the widgets. Was a fix for IE6 odd behaviour.  

See #26117.
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git-svn-id: http://core.svn.wordpress.org/trunk@26182 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Appearance: Fix a PHP Notice when the update transient isn't available (for example, due to a timeout or being used offline). See #25948

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git-svn-id: http://core.svn.wordpress.org/trunk@26183 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Translate the debug update email for development installs. Props Nao for initial patch. See #25667

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git-svn-id: http://core.svn.wordpress.org/trunk@26184 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Themes page: Remove a z-index which caused the Current Theme overlay to overlay menu's, that otherwise appears unused. See #25948 

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git-svn-id: http://core.svn.wordpress.org/trunk@26185 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Widgets: fix the placeholders dimensions so the sidebars don't jump when dragging a widget, see #25821
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git-svn-id: http://core.svn.wordpress.org/trunk@26186 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Themes: Add a get_theme_update_available() function to retrieve an update link and use it on the Themes page. See #26078

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git-svn-id: http://core.svn.wordpress.org/trunk@26187 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Remove the active row theme/plugin styling on Dashboard -> Updates. Fixes #26125

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Inline documentation for hooks in wp-admin/my-sites.php.

Props megane9988, kpdesign.
Fixes #25586.

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git-svn-id: http://core.svn.wordpress.org/trunk@26189 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Widgets: split the sidebars in two containers so there are no empty spaces when they are shown in two columns and some are open, other closed. See #25952.
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git-svn-id: http://core.svn.wordpress.org/trunk@26190 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Widgets: fix html for sidebars columns when the theme has only one sidebar. See #25952.
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