XML-RPC 3.4 methods cleanup

[nacin]

Attached patch does the following:

• Forces _prepare_taxonomy() and _prepare_post_type() to accept a post type or taxonomy object. (You arrays are not welcome here!)
• Limits the return of _prepare_taxonomy() and _prepare_post_type() to a specific type-cast whitelist for things that are potentially useful for mobile apps. The type-casting is important as some arguments can be (or may be in the future) overloaded with arrays, strings, etc. Limiting is important for things like 'capability_type', which is used for registration only; 'rewrite', which can be overloaded and is not something that needs to be exposed to a client, etc. Forwards compatibility is very important to consider. (There is still a filter there, as well.)
• Adds $filter and $fields to _prepare_taxonomy() and therefore wp_getTaxonomies, to match the functionality of wp_getPostTypes. fixes #20407.
• Prevents post types from being changed in _insert_post(). Fixes #20475.
• Removes post_type_supports() checks around comment_status, ping_status, and custom_fields. post_type_supports() handles the admin UI, but should not have any effect on the API. A post type not supporting custom fields (which I'd encourage) would otherwise not be able to have their metadata modified (sad panda).
• Fixes sticky handling. The current code only allows published posts to be stickied. A post can be stickied as long as it is neither private nor password-protected. It now issues an error if the client tries to stick a private post; it will silently unstick a post that is stuck and then changed to be private/protected.
• Unsets tags_input and post_category, as tax_input is also unset already.
• Adds @since's, fixes some docs, trims trailing spaces. Uses rtrim() to remove then force Zulu onto timestamps rather than an str_replace().

With help from maxcutler.

[nacin]

In [20632]:

Clean up the XML-RPC 3.4 methods with regards to consistency and future compatibility.

• Limit returned taxonomy and post type objects to a specific type-cast whitelist of fields.
• Add $filter and $fields to wp.getTaxonomies to match the functionality of wp.getPostTypes.
• Prevent the post type from being chnaged in _insert_post().
• Don't check post_type_supports() in _insert_post().
• Align handling of sticky posts with those of core.
• Force tags and categories to go through terms and terms_names, rather than tags_input and post_category.

fixes #20566. props nacin, maxcutler.

[nacin]

Unit test fixes: ​http://unit-tests.trac.wordpress.org/changeset/700.

[nacin]

In [20635]:

Use correct variable. Caught by unit tests. see #20566.

[SergeyBiryukov]

20566.phpdocs.patch​ adds $fields parameter description for _prepare_taxonomy().

[nacin]

In [20638]:

Add @param for the $fields parameter for XML-RPC's _prepare_taxonomy(). props SergeyBiryukov, fixes #20566.

[batmoo]

There are copy-paste errors in [20632]. Some of the GMT hackery changed the references of $content_struct['date_created_gmt'] to $post_data['post_date_gmt']. This is causing fatal errors:

Fatal error: Call to a member function getIso() on a non-object in /wp-includes/class-wp-xmlrpc-server.php

[nacin]

In [20664]:

Use correct variables. props batmoo. fixes #20566.

[batmoo]

The array keys in [20664] are still incorrect; should be 'date_created_gmt'.

[nacin]

In [20665]:

Use correct variables. props batmoo. fixes #20566.

[nacin]

In [20670]:

Fix copy-paste issues in XML-RPC's _prepare_taxonomy(). see #20566.

[nacin]

In [20671]:

Kill all notices in XML-RPC found when running the test suite with WP_DEBUG. see ​[UT706], ​[UT707]. see #20566.

[nacin]

We should resolve the discrepancy with _prepare_taxonomy() and _prepare_post_type() accepting 'capabilities', 'object_types', etc. but keying the data as 'cap' and 'object_type'. Since we are returning all data exactly how it is keyed in the taxonomy and post type objects, we should make the field groups named the same way.

[nacin]

[20696]

[duck_]

In [20714]:

Declare visibility of _prepare_post_type() as protected. See #20566.

[duck_]

In [20782]:

Minor XML-RPC documentation improvements. See #20566.

Also make newly introduced _is_greater_than_one() private.