Add some unit tests for `is_object_in_term()`.

These tests check a number of the ways that different kinds of values for
`$terms` (integers that match term_id, strings that match term_id or name or
slug) are handled.

See #29467.
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git-svn-id: http://core.svn.wordpress.org/trunk@30204 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `in_object_in_term()`, only check numeric string values against term_id.

The previous `in_array()` check was playing too loose with mixed types, such
that a string like '10_term_name' would incorrectly match a term_id 10.

Props nobinobi, realloc.
Fixes #29467.
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git-svn-id: http://core.svn.wordpress.org/trunk@30205 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add unit tests for `wp_validate_boolean()`.

Props TobiasBg.
See #30238.
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git-svn-id: http://core.svn.wordpress.org/trunk@30206 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Ignore case when checking string 'false' in `wp_validate_boolean()`.

Props TobiasBg, kitchin.
Fixes #30238.
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git-svn-id: http://core.svn.wordpress.org/trunk@30207 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: make it clear that a link is a link in post and comment meta by underlining it on hover or focus

Props morganestes, iamtakashi, fixes #30108


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git-svn-id: http://core.svn.wordpress.org/trunk@30208 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Introduce `term_template` param to `get_the_taxonomies()`.

This parameter allows theme and plugin authors to specify the formatting they
would like on the term links as they are parsed into the taxonomy list.

Props hereswhatidid, dlh, davidjlaietta.
See #27238.
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git-svn-id: http://core.svn.wordpress.org/trunk@30209 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Improve docblocks for `get_the_taxonomies()` and `the_taxonomies()`.

* In `the_taxonomies()`, only document those arguments that are specific to the function. Arguments shared with `get_the_taxonomies()` should be documented in the later function's docblock.
* Add $args hash documentation to `get_the_taxonomies()`.
* Remove the redundant default argument definition in `the_taxonomies()`.

Fixes #27238.
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git-svn-id: http://core.svn.wordpress.org/trunk@30210 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: prevent a flash of visible sub menus before scripts load.

Props mattwiebe, aferica, fixes #30056.


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git-svn-id: http://core.svn.wordpress.org/trunk@30211 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: add a fallback icon for social links where we don't have an icon

Props iamtakashi, fixes #30148


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git-svn-id: http://core.svn.wordpress.org/trunk@30212 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: nicer styles for playlists.

Props iamtakashi, fixes #30163


Built from https://develop.svn.wordpress.org/trunk@30213


git-svn-id: http://core.svn.wordpress.org/trunk@30213 1a063a9b-81f0-0310-95a4-ce76da25c4cd