Update a XIB file due to Xcode upgrade.
Add "View Source" command and window.

Add menu command to view the source text of a loaded page, if the page’s
data type supports it. Add a new window XIB and controller class to
implement the command’s results.

Factor out the code for the application delegate to track new window
controllers, since there are now two kinds of user windows.
Move class's factory function to the class itself.

Move the class-creation method for browser-window controllers from the
application delegate to itself. Update any callers.
Disable line-wrapping for source-view windows.

Enable horizontal scrollbar for source-view windows, but disable it or
the vertical scrollbar whenever scrolling is unnecessary for a given
axis.

Improve horizontal resizing but remove undo support for the source-view
windows’ text-view control. Refine the control’s size limits and bounds
so text lines can be their full width without wrapping. Ensure that the
source text is not editable.
Implement optimized Zoom.
Update more callers of a moved factory method.

Correct missed calls of a method that moved to now use the current
class. (Dynamic dispatch prevents this type of error from being
automatically flagged at compile-time in all circumstances.)
Implement window title bar pop-up menus.

Use the default behavior of window title bar pop-up menus for browser
windows when the current page points to a local file. Otherwise, set
the pop-up menu’s items to start with the current page’s URL, then
strip one path component at a time until the last item is the current
page’s server. When any menu item besides the first is chosen, change
the current page to that item’s URL.

Enable window title bar pop-up menus for source-viewing windows. Set
only one item for said menus, listing the source URL of the text.
Selecting the menu item opens a new browser window that loads the
source URL.