This change allows:
* Engines to update their target rendering surface/size and pixel
format with the backend multiple times during gameplay;
* Users to resize the ScummVM window without having it reset
size/position every time an engine updates its target surface
format;
* Conversions/scaling to continue to run efficiently in hardware,
instead of requiring engines to pick their maximum possible
output format once and upscale inefficiently in software;
* The window to reset size once when an engine calls to set its
initial output size, and to reset again once ScummVM returns to
the launcher.
This is relevant for at least SCI32 and DreamWeb engines, which
perform graphics mode switches during games.
Commit adds kFeatureClipboardSupport. hasTextInClipboard() and
getTextFromClipboard().
OSystem_SDL has this feature if SDL2 is used.
EditableWidget and StorageWizardDialog use g_system to access clipboard
now.
The former code (incorrectly) assumed that the getDefaultGraphicsMode returns
the index in the table returned by getSupportedGraphicsModes. Now the correct
ID is searched and then used.
Ports can add additional special keys.
SDL no longer carries the static tables.
Default behavior unchanged: HardwareInputSet() still gives an empty one.
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.
