Change-Id: I7d75950563dd42b6c3248418187d4cf0bc64e313
Change-Id: I54f66b6de84be9c6a452553267f469af7b523892
This is the final step of the process described at <https://www.mediawiki.org/wiki/Separating_skins_from_core_MediaWiki>. Corresponding core change: Idfc38503. Change-Id: I84fcf7ce6385b8323544cafe6912a00f1886d20d