emscripten: minor refactoring

- Remove the use of EXPORTED_FUNCTIONS in favor of EMSCRIPTEN_KEEPALIVE
- SDL_Delay is no longer aliased to emscripten_sleep

src/sys/ags_text.cpp

@@ -543,7 +543,7 @@ uint16 AGS::convert_hankaku(uint16 code)
 
 extern "C" {
 
-void ags_setAntialiasedStringMode(int on) {
+void EMSCRIPTEN_KEEPALIVE ags_setAntialiasedStringMode(int on) {
 	antialias = on != 0;
 }
 

src/sys/nact.cpp

@@ -489,7 +489,11 @@ void NACT::wait_after_open_menu()
 void NACT::sys_sleep(int ms) {
 	pump_events();
 	ags->update_screen();
+#ifdef __EMSCRIPTEN__
+	emscripten_sleep(ms);
+#else
 	SDL_Delay(ms);
+#endif
 }
 
 // WinMainとのインターフェース

src/sys/nact.h

@@ -418,4 +418,6 @@ protected:
 	uint16 cali2() override;
 };
 
+extern "C" void ags_setAntialiasedStringMode(int on);
+
 #endif // _NACT_H_