This removes the need to convert the parameter to copyRectToScreen to
"const byte *", which is commonly used in games, which use Graphics::Surface
to store their graphics data.
All uses of the old target scale API actually wanted to disallow scaling of
the mouse cursor. This commit adapts our API to this and thus simplifies
backend implementations.
Some backends, most notable the Wii and Android, did some implementation of
the cursor target scale, which I didn't adapt yet. I added a TODO for the
porters there.
This gets rid of the hacks, where SdlEventSource added events with custom type
numbers to pass SDL_VIDEOEXPOSE and SDL_VIDEORESIZE to the graphics manager.
Furthermore it get rids of the uninituitive and hard to trace way of assigning
the proper mouse coordinates to mouse related events. Formerly it passed the
real screen coordinates through the even dispatching api to the graphics
manager (at least hopefully ;-) and let that handle creating a new event with
the proper coordinates. Now instead SdlEventSource handles the proper
coordinate setup itself.
Since this is a behavior change and I can not test all the SDL based small
devices ports this commit might break compilation for them and more serve it
might also break mouse position behavior. If any of that occurs I am sorry
about it.
