content-view-factory now has a ._createAttachmentsView method, and can be passed opts.createAttachmentsView on construction to override
Prototype GalleryOnFocusView to encapsulate the tiled->gallery inline behavior with no modal
GalleryOnFocusView doesn't automatically act on focusContent.hub. But he has a .focus method that can be used to focus an attachment
Update tests for removal of ContentView.showAttachmentsGallery