Recent Posts Widget: Use `ob_end_flush()` instead of `ob_flush()`.

`ob_end_flush()` flushes the output buffer *and* turns output buffering off, same as `ob_get_flush()`.

props m_i_n.
see #28009 for trunk.


git-svn-id: https://develop.svn.wordpress.org/trunk@28195 602fd350-edb4-49c9-b593-d223f7449a82
Force users to choose a nav menu in the custom nav menu widget, for a better customizer UX

Before, they had to make a dummy change to get it to render. Now they
are made to choose a nav menu from the dropdown, which feels more
natural.

fixes #27878 for trunk. props westonruter

git-svn-id: https://develop.svn.wordpress.org/trunk@28197 602fd350-edb4-49c9-b593-d223f7449a82
Use '&mdash; Select &mdash;' instead of '-- Select --' for nav menus. Looks nicer.

see #27878

git-svn-id: https://develop.svn.wordpress.org/trunk@28205 602fd350-edb4-49c9-b593-d223f7449a82
Ensure the `nav_menu_meta_box_object` filter hook is only documented once.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28207 602fd350-edb4-49c9-b593-d223f7449a82
Ensure the `register` filter hook is only documented once.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28208 602fd350-edb4-49c9-b593-d223f7449a82
Ensure the `style_loader_tag` filter hook is only documented once.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28209 602fd350-edb4-49c9-b593-d223f7449a82
Ensure the `submitlink_box` action hook is only documented once.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28210 602fd350-edb4-49c9-b593-d223f7449a82
Ensure adjacency of a duplicate hook comment for a `the_category` filter call.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28211 602fd350-edb4-49c9-b593-d223f7449a82
Ensure all duplicate calls of the `wp_create_file_in_uploads` filter are labeled as such.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28212 602fd350-edb4-49c9-b593-d223f7449a82
Ensure the `wp_edit_nav_menu_walker` filter is only documented once.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28213 602fd350-edb4-49c9-b593-d223f7449a82
Ensure the `wp_set_comment_status` action hook is only documented once.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28214 602fd350-edb4-49c9-b593-d223f7449a82
Clean up duplicate hook notations and adjacency for calls to the `wp_signup_location` filter.

Also adds braces missed in [25535].

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28215 602fd350-edb4-49c9-b593-d223f7449a82
Mark the `$hook` and `$page_hook` hooks as `@internal` to skip parsing.

See #26869.


git-svn-id: https://develop.svn.wordpress.org/trunk@28216 602fd350-edb4-49c9-b593-d223f7449a82
Recent Posts Widget: Use `ob_end_flush()` instead of `ob_flush()`.

`ob_end_flush()` flushes the output buffer *and* turns output buffering off, same as `ob_get_flush()`.

props m_i_n.
see #28009 for trunk.


git-svn-id: https://develop.svn.wordpress.org/trunk@28217 602fd350-edb4-49c9-b593-d223f7449a82