Use proper non-capturing regex syntax for YouTube in `wp_video_shortcode()`.

Props Fab1en.
See [27063].
Fixes #29119.

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Don't show the Featured Image metabox for users with the `contributor` role. Do enqueue media so that TinyMCE previews work for YouTube embeds, etc.

Props SergeyBiryukov.
Fixes #28327.

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git-svn-id: http://core.svn.wordpress.org/trunk@29180 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `media.view.BulkSelectionActionButton.click()`, do not assume that `delete` is the only possible bulk action.

Fixes #29101.

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git-svn-id: http://core.svn.wordpress.org/trunk@29181 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Ignore entities in XML-RPC requests.

props mdawaffe, nacin.

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git-svn-id: http://core.svn.wordpress.org/trunk@29182 1a063a9b-81f0-0310-95a4-ce76da25c4cd
4.0-beta3

Built from https://develop.svn.wordpress.org/trunk@29414


git-svn-id: http://core.svn.wordpress.org/trunk@29192 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Media Grid: display upload errors in a dismissable sidebar.

See #29037.

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git-svn-id: http://core.svn.wordpress.org/trunk@29193 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Media Grid: after [28996], use the same cover size for audio/video files that images use for thumbnails.

See #24716.

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git-svn-id: http://core.svn.wordpress.org/trunk@29194 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Media Grid: expose the `$.Deffered()` object in `media.view.AttachmentsBrowser.updateContent()` so the grid can call `Backbone.history.start()` when models actually exist. 

This is a lot better then `_.delay( this.pray, 1000 )`, but needs continued study.

See #29052.

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git-svn-id: http://core.svn.wordpress.org/trunk@29198 1a063a9b-81f0-0310-95a4-ce76da25c4cd
After [29339] and [29341], add more unit tests and less ambiguous type-checking before bailing in meta-related functions that expect a numeric value for `$object_id`.

Props SergeyBiryukov.
Fixes #28315.

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git-svn-id: http://core.svn.wordpress.org/trunk@29199 1a063a9b-81f0-0310-95a4-ce76da25c4cd
After [28883], ensure that priorities have callbacks before returning `true` in `has_filter()`.

Adds unit tests.

Props boonebgorges.
Fixes #29070.

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`WP_List_Table::items` should be `public`, not `protected`. It is accessed in a subclass directly via `wp_ajax_get_comments()`.

See [28493].
Fixes #29072.

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git-svn-id: http://core.svn.wordpress.org/trunk@29201 1a063a9b-81f0-0310-95a4-ce76da25c4cd
After [29201], use `aria-label` instead of `aria-labelledby` in `WP_Plugin_Install_List_Table::display_rows()`.

Props nvwd, DrewAPicture.
Fixes #28853.

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Media Grid: reduce the padding for `.attachments`.

Props ocean90, ryelle.
Fixes #29085.

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git-svn-id: http://core.svn.wordpress.org/trunk@29203 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `media.view.AttachmentFilters.All`, make `uploaded` conditional upon `media.view.settings.post.id` and include a new filter: `unattached`.

Drop the `mime-types` filter and related class (which was added for Media Grid) and use `all` instead. 

Props ocean90, wonderboymusic.
Fixes #29065.

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git-svn-id: http://core.svn.wordpress.org/trunk@29204 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Media Grid: remove some unused Trash/Delete handler logic. Rendered useless since [29266] and made official by [29322].

See #28819.

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git-svn-id: http://core.svn.wordpress.org/trunk@29205 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Media Grid: add screen reader labels with more context to filters and bulk actions. Ditto for list view.

Props afercia.
Fixes #29026.

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git-svn-id: http://core.svn.wordpress.org/trunk@29206 1a063a9b-81f0-0310-95a4-ce76da25c4cd
MediaElement upgrade: cleanup for generated markup for videos. 

See #29110.

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git-svn-id: http://core.svn.wordpress.org/trunk@29207 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Video: use `auto` instead of actual height for the responsive wrapper in generated markup.

See #29110.

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git-svn-id: http://core.svn.wordpress.org/trunk@29208 1a063a9b-81f0-0310-95a4-ce76da25c4cd