Log Message:
SDL2: update to 2.28.0.

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2.28.0:
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General:
* Added SDL_HasWindowSurface() and SDL_DestroyWindowSurface() to switch between \ 
the window surface and rendering APIs
* Added a display event SDL_DISPLAYEVENT_MOVED which is sent when the primary \ 
monitor changes or displays change position relative to each other
* Added the hint SDL_HINT_ENABLE_SCREEN_KEYBOARD to control whether the \ 
on-screen keyboard should be shown when text input is active