Update OOjs UI to v0.1.0-pre (99ec31d9b9)

New changes:
6298415 ButtonWidget: Fix titled button
918ebed MediaWiki theme: Fix styling of SearchWidget
bd03644 Refine global event handling in non-isolated window managers
9a7633c WindowManager: Wait for window to open before trying to close it
5516490 Element: Correct method name reference in documentation
99ec31d Position popups and their anchors correctly in RTL

Change-Id: I4266c58ec1a2e6cee54ffc55891a5c2097f0222f
Merge "Update OOjs UI to v0.1.0-pre (99ec31d9b9)"