Customizer: Add support for the media library in Background Image controls.

`WP_Customize_Upload_Control` (PHP) and `api.UploadControl` (JS) can now open the media modal.

props celloexpressions, and ericlewis for docs.
see #21483.
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git-svn-id: http://core.svn.wordpress.org/trunk@30308 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Always use a full filesystem path when including the FTP handler in PemFTP. This prevents other files in the includes directory being scanned/included accidentally.
See #29628

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PHP 5.2 compatibility for [30310], __DIR__ wasn't added until PHP 5.3. Props TobiasBg. Fixes #29628

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git-svn-id: http://core.svn.wordpress.org/trunk@30310 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: clean up sprintf from template tags and use the correct escaping for twentyfifteen template tags.

Props aprea, obenland, fixes #30319


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Use a brighter blue against dark backgrounds in the admin menu and toolbar.

Not only does this pass contrast guidelines, but it also visually appears closer to the original highlight blue used against light backgrounds.

props melchoyce. fixes #30323.

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git-svn-id: http://core.svn.wordpress.org/trunk@30312 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: adding context to page links for screenreaders.

Props afercia, fixes #30174.


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git-svn-id: http://core.svn.wordpress.org/trunk@30313 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: since color schemes can be customized let's call them base color schemes instead of just color schemes.

Props celloexpressions, iandstewart, fixes #30316


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git-svn-id: http://core.svn.wordpress.org/trunk@30314 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: adding context to pagination links for screenreaders.

Props afercia, iamtakashi, fixes #30152


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git-svn-id: http://core.svn.wordpress.org/trunk@30315 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: improve appearance of page links when there are tons of pages to link to

Props iamtakashi, fixes #30301


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git-svn-id: http://core.svn.wordpress.org/trunk@30316 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: enhance the inline toolbar for images:
- Add alignment (left, center, right, none) buttons.
- Position the menu above the image when possible, except on iOS.
- Fix selecting images on iOS.
First run, part props avryl. See #30147.
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git-svn-id: http://core.svn.wordpress.org/trunk@30317 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix typo in translatable string, see #30147.

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git-svn-id: http://core.svn.wordpress.org/trunk@30318 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Manually delete fixture in `test_mysqli_flush_sync()`.

This test creates a dummy post and subsequently runs a query containing
`DROP PROCEDURE`. This latter query implies a `COMMIT`, which means that the
post is not cleaned up for later tests. Manually deleting the post with
`wp_delete_post()` solves this problem.

Fixes #28155.
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git-svn-id: http://core.svn.wordpress.org/trunk@30319 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: reduce the margins on the editor body in esitor-style.css. Fixes #30331.
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git-svn-id: http://core.svn.wordpress.org/trunk@30320 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Introduce `$post_type` param for `count_user_posts()`.

Props Caspie, engelen, DrewAPicture.
Fixes #21364.
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git-svn-id: http://core.svn.wordpress.org/trunk@30321 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Pass query object to 'the_post' filter.

Props tlovett1.
Fixes #30327.
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git-svn-id: http://core.svn.wordpress.org/trunk@30322 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: unfix the sidebar if we have a menu with submenus as there is a chance visitors might not be able to scroll down to see submenus in some situations.

Props mattwiebe, fixes #30208.


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git-svn-id: http://core.svn.wordpress.org/trunk@30323 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: cleaning up JS introduced in r30305 that doesn't pass jshint.

Props boonebgorges, fixes #29988.


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git-svn-id: http://core.svn.wordpress.org/trunk@30324 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Customizer: Prevent double-encoding in `WP_Customize_Control`.

Control's label and description may include HTML.

fixes #29572.
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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.
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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.
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git-svn-id: http://core.svn.wordpress.org/trunk@30327 1a063a9b-81f0-0310-95a4-ce76da25c4cd