Android life cycle behavior more closely matches iOS

This change also decouples the pause/resume handling from the video subsystem on Android, so applications that don't use SDL for video can get application life cycle events.

The semantics for the life cycle events are that they need to be handled in an event watch callback, and once they've been delivered, the application will block until it's been resumed. SDL_HINT_ANDROID_BLOCK_ON_PAUSE can be used to control that behavior, and if that's set to "0", then the application will continue to run in the background at low CPU usage until being resumed or stopped.

SDL_HINT_ANDROID_BLOCK_ON_PAUSE_PAUSEAUDIO has been removed, and the audio will be paused when the application is paused.

Fixes https://github.com/libsdl-org/SDL/issues/3193

src/SDL.c

@@ -52,6 +52,7 @@
 #include "thread/SDL_thread_c.h"
 #include "video/SDL_pixels_c.h"
 #include "video/SDL_video_c.h"
+#include "video/android/SDL_androidevents.h"
 #include "filesystem/SDL_filesystem_c.h"
 
 #define SDL_INIT_EVERYTHING ~0U
@@ -225,6 +226,10 @@ int SDL_InitSubSystem(Uint32 flags)
 
     SDL_InitMainThread();
 
+#ifdef SDL_PLATFORM_ANDROID
+    Android_InitEvents();
+#endif
+
 #ifdef SDL_USE_LIBDBUS
     SDL_DBus_Init();
 #endif
@@ -571,6 +576,10 @@ void SDL_Quit(void)
     SDL_DBus_Quit();
 #endif
 
+#ifdef SDL_PLATFORM_ANDROID
+    Android_QuitEvents();
+#endif
+
     SDL_SetObjectsInvalid();
     SDL_ClearHints();
     SDL_AssertionsQuit();