Add cache invalidation when updating a term, example: create a category, assign it to a post, edit the category. Currently, the post's term cache is not updated. When updating terms in a given taxonomy, invalidate the object term caches linked to that taxonomy. 

Introduce `get_taxonomy_last_changed()`, `set_taxonomy_last_changed()`, and `post_taxonomy_is_fresh()`.

`post_taxonomy_is_fresh()` is only called in `get_object_term_cache()` - at which point the taxonomy's `last_changed` value is checked against the post's `{$taxonomy}_last_changed` value.

`set_taxonomy_last_changed()` is called whenever directory database queries are made that insert new terms or affect existing terms.

Fixes #22526.


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git-svn-id: http://core.svn.wordpress.org/trunk@26970 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Regenerate the term hierarchy cache (`{taxonomy}_children`) when it is out of sync with the passed taxonomy's `last_changed` value.

Introduces `taxonomy_hierarchy_is_fresh()`, which is only called in `_get_term_hierarchy()`. The taxonomy's `last_changed` value is checked against the value of `wp_cache_get( 'hierarchy_last_changed', $taxonomy )`.

Adds a unit test - `Tests_Term:test_hierachy_invalidation()`.

See [27101], which makes this type of cache invalidation possible.
Fixes #14485.


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JSHint fixes for media-views and Gruntfile.

props gcorne.
fixes #27032, #27033.

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Merge colors.css into wp-admin.css. Non-default color schemes became overloads rather than swaps in the 3.8 redesign. Benefits include:

* No more border-width, border-style, border-color insanity.
* Point releases are much less likely to require extra finagling to avoid rebuilding the color schemes.
* Yours truly has a better overall vision of ~14,000 lines of admin CSS and where we go from here.

1,065 net lines of red, y'all.
props helen, jorbin. fixes #18380.

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Some tweaks to [27106]:

* Add more @todo markings and remove one that's been resolved.
* Restore a missing comma in a `.wp-badge` background rule, and add a comment reminding us why it's there.

see #18380.

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In `get_terms()`, don't set automatically `hierarchical` to `false` when `parent => 0` is passed. The default value for `parent` is `''`.

In `_get_term_children()`, don't skip a top-level term without first including its children in the returned term list. Ironically, the call to `_get_term_children()` in `get_terms()` has a comment stating `"Make sure we show empty categories that have children."`, but it didn't work if you were retrieving top-level categories only.

All unit tests pass. Added a unit test based on the use case described in this ticket.

Fixes #26903.


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Fix some hover/focus styling and specificity issues. see #18380.

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git-svn-id: http://core.svn.wordpress.org/trunk@26976 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix scrolling inside the Visual editor on MacOS, add the same functionality to the Text editor, see #27013
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Fix the conditional enqueueing/printing of colors stylesheets, without breaking dependencies.

fixes #18380.
see #20729 which should properly fix this.

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Network install: When showing the path to wp-config.php make sure our slashes are normalized.

props VarunAgw.
fixes #27025.

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Add imgur to the list of oEmbed providers.

props bradparbs.
fixes #21632.

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Revisions browser: The back button should return to the post you were editing (use replaceState instead of pushState).

props adamsilverstein.
fixes #26997.

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