Replace the old device_iterator and its specialized versions with functionally equivalent classes that use standard operators to yield references to devices/interfaces rather than pointers. With range-based for loops, they no longer have to be stored in named variables, though they can also be reused concurrently since the iteration state is now maintained by a subclass.
Add a few more typical getters to device_t::subdevice_list.
It's damn slow, ~50ms/frame on cdkong. Caching and/or hw accel will
solve that easily. It doesn't look very good, nanosvg need better
anti-aliasing. It also doesn't do texturing very well and images not
at all, so some of our current svgs won't look good. But all that's
fixable.
C++11 range-based for loops can now iterate over simple_list, tagged_list, core_options, device_t::subdevice_list, device_t::interface_list, render_primitive_list and all subclasses of the above, and much code has been refactored to use them. Most core classes that have these lists as members now have methods that return the lists themselves, replacing most of the methods that returned the object at an owned list's head. (A few have been retained due to their use in drivers or OSD.)
device_t now manages subdevice and interface lists through subclasses, but has given up the work of adding and removing subdevices to machine_config.
memory_manager has its tagged lists exposed, though the old rooted tag lookup methods have been removed (they were privatized already).