Code review comment for lp:~mir-team/mir/cursor-spike-phase-1-resubmit

3. Fixed. Whoops! Lost track during refactoring and was returning a nullptr rather than a null cursor instance.
4. Im still not sure what we mean here. mir::graphics::Buffer is a GPU side buffer (which could be mapped). mir::graphics::CursorImage is just a way to access (CPU side, for example for upload to a buffer), the pixels of a loaded cursor image (loaded from the on disk theme). Maybe you mean mir::graphics::PixelBuffer. In this case I agree there is a common mg::Image/mg::Pixels interface they implement (raw_argb, size). Of course we shouldnt get overexcited about making classes implement interfaces until we have someone who wishes to consume them through that interface.
5. What loads the Cursor theme then?
6. I chose string/string on the suggestion of RAOF...and that afaik it is what toolkits will be best prepared to deal with (working like other cursor APIs).