Customizer: Prevent double-encoding in `WP_Customize_Control`.

Control's label and description may include HTML.

fixes #29572.
Built from https://develop.svn.wordpress.org/trunk@30326


git-svn-id: http://core.svn.wordpress.org/trunk@30325 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Improve keyboard accessibility on Custom Header and Custom Background screen.

props florianziegler.
fixes #29289.
Built from https://develop.svn.wordpress.org/trunk@30327


git-svn-id: http://core.svn.wordpress.org/trunk@30326 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Correct `@since` tag in `count_user_posts()` docs.

Props pavelevap, DrewAPicture.
See #21364.
Built from https://develop.svn.wordpress.org/trunk@30328


git-svn-id: http://core.svn.wordpress.org/trunk@30327 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Customizer: Improve ability to filter active state for widget area Customizer sections.

* Mark panels, sections, controls as active if preview explicitly indicates.
* Introduce `WP_Customize_Sidebar_Section` PHP class, and `SidebarSection` JS class.
* Move logic for determining whether a sidebar section is active from the `SidebarControl` to `SidebarSection`.

props westonruter.
fixes #30235.
Built from https://develop.svn.wordpress.org/trunk@30329


git-svn-id: http://core.svn.wordpress.org/trunk@30328 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Color Picker: Allow to override `mode` and `width` values for Iris via wpColorPicker options.

props jtsternberg.
fixes #30182.
Built from https://develop.svn.wordpress.org/trunk@30330


git-svn-id: http://core.svn.wordpress.org/trunk@30329 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: Add a transparent border to a link in the footer to avoid jumpiness on hover.

props iamtakashi.
fixes #30332.
Built from https://develop.svn.wordpress.org/trunk@30331


git-svn-id: http://core.svn.wordpress.org/trunk@30330 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix selector for the "Live Widget Previews" feature pointer.

props rzen.
fixes #30158.
Built from https://develop.svn.wordpress.org/trunk@30332


git-svn-id: http://core.svn.wordpress.org/trunk@30331 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Introduce a button on the user profile screen which clears all other sessions, and on the user editing screen which clears all sessions. Only appears when there are applicable sessions which can be cleared.

See #30264.
Props jorbin, ocean90, johnbillion


Built from https://develop.svn.wordpress.org/trunk@30333


git-svn-id: http://core.svn.wordpress.org/trunk@30332 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Improvements to [30333]:

* Move `.hide-if-no-js` class to table row
* Add a wrapper class
* Add missing translators comment

see #30264.
Built from https://develop.svn.wordpress.org/trunk@30334


git-svn-id: http://core.svn.wordpress.org/trunk@30333 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Site Language: Install translations on the fly.

The language dropdown now includes installed languages and all available translations when the filesystem is writable by WordPress.
Go to wp-admin/options-general.php, select one of the available translations, submit the form and let WordPress handle the rest.
Works for Multisite's Default Language too.

see #29395.
Built from https://develop.svn.wordpress.org/trunk@30335


git-svn-id: http://core.svn.wordpress.org/trunk@30334 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Don't split shared terms on term update.

Splitting shared terms means assigning a new term_id to a given term_taxonomy_id.
It was uncovered that this change could cause problems for sites that have
cached the original term_id somehow - say, in postmeta - since future lookups
using that term_id will now fail.

Removing for 4.1-beta1. We'll look at improvements to backward compatibility
to try to get this back into a later beta.

Props mboynes.
See #30335.
Built from https://develop.svn.wordpress.org/trunk@30336


git-svn-id: http://core.svn.wordpress.org/trunk@30335 1a063a9b-81f0-0310-95a4-ce76da25c4cd
When asserting microtime output as a number, make it a number

microtime is by default a string. Doing a greater then or less than check of that string is a bad idea since it uses the first part (the micro part of microtime) rather then the actual time. This adds a helper to convert microtime output into a float which we can then use to properly compare the output of microtime.

This fixes an intermittent test failure.

fixes #30336


Built from https://develop.svn.wordpress.org/trunk@30337


git-svn-id: http://core.svn.wordpress.org/trunk@30336 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Introduce Distraction-Free Writing v2, a re-think of DFW that uses the main editor instance

* the "DFW" button is now an auto/off toggle
* defaulting to auto during beta, decide later for release
* "auto" means that DFW gets enabled as you start typing in editor
* tabbing and mousing out will bring the full interface back
* there is a slight grace period during which your mouse can quickly return

Feature plugin work happened here: https://github.com/avryl/focus

props avryl, azaozz, Michael Arestad
fixes #29806
Built from https://develop.svn.wordpress.org/trunk@30338


git-svn-id: http://core.svn.wordpress.org/trunk@30337 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: set the image toolbar's z-index higher than the editor when the new DFW is active. See #30147.
Built from https://develop.svn.wordpress.org/trunk@30339


git-svn-id: http://core.svn.wordpress.org/trunk@30338 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Only use the 'Installed' optgroup in wp_dropdown_languages() if it's needed.

see #30335.

Built from https://develop.svn.wordpress.org/trunk@30340


git-svn-id: http://core.svn.wordpress.org/trunk@30339 1a063a9b-81f0-0310-95a4-ce76da25c4cd