Add OakTabItemView to be used in upcoming OakTabBarView
Update OakTabBarView class to use an NSView per tab item
HOBrowserView: Avoid calling super on key events

This workaround is to avoid a couple of undesired behaviors in the `HTMLOutputWindow` when the web page implements keyboard commands such as Git → Browse Annotated File (Blame). Namely, when using the keyboard commands, we would always receive an NSBeep. Also, fixed an issue when these key commands may conflict with menu keys. See comment in the commit for details.
Workaround for weak pointers to NSWindow crashing on 10.7
Make window key in actions that show file browser field editor

It is possible to bring up menus for inactive windows and e.g. select Rename or Duplicate.