As of r17600 - all backend Javascript is broken.

[sterlo]

Did a fresh install from the trunk...went to the backend and noticed that all the awesome UI things like clicking the arrow to expand menu items on the left...had stopped working.

No errors are being thrown. I am looking into what revision specifically caused this.

[kawauso]

Introduced in [17596] as includes_url() isn't available in script-loader.php:

Fatal error:  Call to undefined function includes_url() in wp-includes/script-loader.php on line 196

[nacin]

(In [17608]) Revert [17596] for now. props kawauso, see #17057, see #17050.

[dd32]

(In [17609]) Revert [17608] adding back [17596] and actually include the dummy function this time. See #17057 Fixes #17050