Clarify inline documentation for the `_is_valid_nav_menu_item()` and `wp_get_nav_menu_items()` in wp-includes/nav-menu.php.

Props morganestes for the initial patch.
Fixes #29914.

Built from https://develop.svn.wordpress.org/trunk@29868


git-svn-id: http://core.svn.wordpress.org/trunk@29628 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add missing labels to category filter dropdowns.

props afercia.
fixes #29921.
Built from https://develop.svn.wordpress.org/trunk@29870


git-svn-id: http://core.svn.wordpress.org/trunk@29629 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Remove "View" prefix from category filter dropdowns, for consistency with [27626].

props afercia.
see #29921.
Built from https://develop.svn.wordpress.org/trunk@29871


git-svn-id: http://core.svn.wordpress.org/trunk@29630 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add missing label to comment type filter dropdown.

props afercia.
fixes #29922.
Built from https://develop.svn.wordpress.org/trunk@29872


git-svn-id: http://core.svn.wordpress.org/trunk@29631 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix whitespace issues in [29781]. Remove a redundant comment.

props miqrogroove.
see #29557.
Built from https://develop.svn.wordpress.org/trunk@29873


git-svn-id: http://core.svn.wordpress.org/trunk@29632 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Media modal: fix reordering of the thumbnails while creating or editing a gallery, props avryl, fixes #29606 for trunk. 
Built from https://develop.svn.wordpress.org/trunk@29876


git-svn-id: http://core.svn.wordpress.org/trunk@29633 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Differentiate between invalid and missing admin emails when adding a new site

Check the emptiness of the admin email before using `sanitize_email()` and `is_email()` to determine if the address is valid.

Fixes #17890

Built from https://develop.svn.wordpress.org/trunk@29877


git-svn-id: http://core.svn.wordpress.org/trunk@29634 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Quicktags: remove `accesskey` attributes the buttons and don't add empty `title` attributes, fixes #29358
Built from https://develop.svn.wordpress.org/trunk@29878


git-svn-id: http://core.svn.wordpress.org/trunk@29635 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix support for the `hide` option in wpColorPicker, props tollmanz, fixes #29632
Built from https://develop.svn.wordpress.org/trunk@29879


git-svn-id: http://core.svn.wordpress.org/trunk@29636 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Do not send a welcome notification when noconfirmation has been flagged

When adding a new user to a site on the network, 2 emails are sent out - one for confirmation and one as a welcome. If the option for no confirmation is selected, neither should send.

props transom
Fixes #16235

Built from https://develop.svn.wordpress.org/trunk@29880


git-svn-id: http://core.svn.wordpress.org/trunk@29637 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Avoid PHP notices if 'plugin' is not set for tab=plugin-information.

props avryl.
fixes #29936.
Built from https://develop.svn.wordpress.org/trunk@29882


git-svn-id: http://core.svn.wordpress.org/trunk@29638 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: fix the 'wpgallery' plugin to use a placeholder for galleries when either the 'wpview' plugin or wp.mce is not loaded. Fixes #28756
Built from https://develop.svn.wordpress.org/trunk@29883


git-svn-id: http://core.svn.wordpress.org/trunk@29639 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Quicktags: move focusing the editor after inserting content to the end of the code blocks. Fixes a bug in Chrome where both the textarea and the window may auto-scroll to unexpected position on clicking a Quicktags button. Part props avryl, fixes #29944 for trunk.
Built from https://develop.svn.wordpress.org/trunk@29884


git-svn-id: http://core.svn.wordpress.org/trunk@29640 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Don't create dummy data for each date query test.

The integration tests for using date_query in WP_Query require the creation of
dummy post data, much of which is common between a number of tests. However,
newer tests do not require as much data, so to reduce overhead we create the
data explicitly only when we need it, instead of in the setUp() method.

See #29781.
Built from https://develop.svn.wordpress.org/trunk@29885


git-svn-id: http://core.svn.wordpress.org/trunk@29641 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Editor-expand: reset the editor height after the window is resized. Fixes #29952 for trunk.
Built from https://develop.svn.wordpress.org/trunk@29886


git-svn-id: http://core.svn.wordpress.org/trunk@29642 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Introduce support for nested queries in WP_Meta_Query.

Previously, meta query arguments could be joined by a single AND or OR relation.
Now, these queries can be arbitrarily nested, allowing clauses to be linked
together with multiple relations.

Adds unit tests for the new nesting syntax. Modifies a few existing unit tests
that were overly specific for the old SQL syntax. Backward compatibility with
existing syntax is fully maintained.

Props boonebgorges, DrewAPicture.
See #29642.
Built from https://develop.svn.wordpress.org/trunk@29887


git-svn-id: http://core.svn.wordpress.org/trunk@29643 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Use assertEqualSets() for a few taxonomy-related tests.

assertEquals() was causing problems in environments where the tests take more
than one second to run, thereby causing results to be returned in the incorrect
order.
Built from https://develop.svn.wordpress.org/trunk@29888


git-svn-id: http://core.svn.wordpress.org/trunk@29644 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Quicktags: fix strict check for `instance['0']`, props afercia, fixes #29767
Built from https://develop.svn.wordpress.org/trunk@29889


git-svn-id: http://core.svn.wordpress.org/trunk@29645 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Use only LEFT JOINs when a meta_query contains a NOT EXISTS clause.

Mixing LEFT and INNER JOIN in these cases results in posts with no metadata
being improperly excluded from results.

Props johnrom.
Fixes #29062.
Built from https://develop.svn.wordpress.org/trunk@29890


git-svn-id: http://core.svn.wordpress.org/trunk@29646 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Introduce support for nested queries in WP_Tax_Query.

Previously, tax query arguments could be joined by a single AND or OR relation.
Now, these queries can be arbitrarily nested, allowing clauses to be linked
together with multiple relations.

In a few places, WP_Query runs through a list of clauses in a tax_query in order
to set certain query vars for backward compatibility. The necessary changes have
been made to WP_Query to support this feature with the new complex structure of
tax_query. Unit tests are included for these backward compatibility fixes.

Unit tests for the new nesting syntax are included.

Props boonebgorges.
Fixes #29718. See #29738.
Built from https://develop.svn.wordpress.org/trunk@29891


git-svn-id: http://core.svn.wordpress.org/trunk@29647 1a063a9b-81f0-0310-95a4-ce76da25c4cd