SDL3 → common Relation

File in client/SDL/SDL3	Includes file in client/SDL/common
SDL3/sdl_freerdp.cpp	sdl_prefs.hpp
SDL3/sdl_freerdp.cpp	aad / sdl_webview.hpp
SDL3/sdl_kbd.cpp	sdl_prefs.hpp
dialogs / res / sdl3_resource_manager.hpp	res / sdl_resource_manager.hpp