Added missing line to make things compile.

src/video/win32/SDL_win32keyboard.c

@@ -125,6 +125,7 @@ WIN_QuitKeyboard(_THIS)
 void
 WIN_StartTextInput(_THIS)
 {
+	SDL_Window *window = SDL_GetKeyboardFocus();
 	HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;
 
 }