This reverts commit 2f54b101.

#500866 by boombatower, solotandem: Remove t() from assertion messages in SimpleTest, so translators do not get 1000s of bogus strings.

#331951 by aspilicious, sun, jhodgdon, Morbus, et al: Figure out and apply coding standard for casting.

- Patch #265973 by Damien Tournoud, mr.baileys, dixon_, clemens.tolboom: XML-RPC chokes with long server response.

- Patch #647336 by boombatower, Morbus Iff: fixed bug with when xmlrpc() is called with no function arguments. Added some extra XML-RPC tests.

#497118 by chx, catch, pwolanin, JoshuaRogers, and Jacob Singh: Remove the function registry. While the hope was that this would result in improved performance for low-end hosts, it comes at the expense of critical development experience problems and less benefit than something like APC. Class registry remains intact to facilitate autoloading.

Of all the patches to accidentally commit without a message. :( Rolling back registry rip. Let's try that again.

#376129 by boombatower, Damien Tournoud, and chx: Change getInfo() to a static method to reduce memory footprint of SimpleTest.

- Patch #302763 by Dave Reid, Rob Loach: replace time() by ['REQUEST_TIME'] as per Rasmus' suggestion.  Removed drupal_referrer() for consistency.

- Patch #268063 by boombatower, chx, cwgordon7, Damien Tournoud: move includes/tests to simpletest/tests and provide hidden .info propery

- Patch #151902 by MadHarold et al: a better format_size() (and removed some excessive white space).

- Patch #251473 by webchick, chx, et al: one step closer to running tests in the includes directory.  Not working yet.

  Drupal core!  This is an important milestone for the project so enable
  the module and check it out ... :)

  Thanks to Rok Žlender, Károly Négyesi, Jimmy Berry, Kevin Bridges, Charlie
  Gordon, Douglas Hubler, Miglius Alaburda, Andy Kirkham, Dimitri13, Kieran
  Lal, Moshe Weitzman, and the many other people that helped with testing
  over the past years and that drove this home.

  It all works but it is still rough around the edges (i.e. documentation
  is still being written, the coding style is not 100% yet, a number of
  tests still fail) but we spent the entire weekend working on it in Paris
  and made a ton of progress.  The best way to help and to get up to speed,
  is to start writing and contributing some tests ... as well as fixing
  some of the failures.

  For those willing to help with improving the test framework, here are
  some next steps and issues to resolve:

    - How to best approach unit tests and mock functions?
    - How to test drupal_mail() and drupal_http_request()?
    - How to improve the admin UI so we have a nice progress bar?
    - How best to do code coverage?
    - See http://g.d.o/node/10099 for more ...