* Expand the `wptexturize()` RegEx to include the list of registered shortcodes.
* Avoid backtracking after `[` chars by not filtering params in registered shortcodes. This will cause escaped shortcodes and their params to become texturized if not registered.
* Registered shortcode params will never be texturized, even when escaped.
* Move all tests involving unregistered shortcodes to a new and improved unit.
* Update one test involving HTML within shortcode params.
Props miqrogroove.
See #29557.
git-svn-id: https://develop.svn.wordpress.org/trunk@29748 602fd350-edb4-49c9-b593-d223f7449a82