Make the ‘expanded’ property of OakTabBarView private
Add identifier to OakTabBarViewDataSource
NSBox is an implementation detail so use NSView instead
Introduce OakBackgroundFillView which replaces NSBox for dividers

This view has an active/inactive color or image. The latter is drawn as a pattern color (tiled image).
Add OakRolloverButton
Add tab images from Safari
Add “create tab” images from MMTabBarView
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.
Reload tabs before changing selected tab index

This worked previously because selected tab was stored using an index and we were only changing it (before reload) when closing tabs, so the new index would be valid both before and after reload.

With the new OakTabBarView the index of selected tab is instantly converted into a reference to a tab item.
Don’t ignore case changes on case-insensitive file systems
By default we no longer show the tab bar for a single document

Once we have two documents (in same window) we show the tab bar and never hides it again (to avoid content from jumping.
Fix reappearing regular expression error popover

If it was shown and dismissed, then it would show again the next time the text field content was changed (and the content was not a valid expression).