Fixed memory leak if logging is done after SDL_Quit()

If someone calls SDL_Quit(), then runs an SDL function that implicitly initializes TLS or logging, and then calls SDL_Quit() again, we want to make sure we run through the quit process again. Each of the Init/Quit calls are protected against being called multiple times.

src/SDL.c

@@ -113,7 +113,6 @@ static SDL_bool SDL_MainIsReady = SDL_FALSE;
 #else
 static SDL_bool SDL_MainIsReady = SDL_TRUE;
 #endif
-static SDL_bool SDL_main_thread_initialized = SDL_FALSE;
 static SDL_bool SDL_bInMainQuit = SDL_FALSE;
 static Uint8 SDL_SubsystemRefCount[32];
 
@@ -186,33 +185,21 @@ void SDL_SetMainReady(void)
 /* Initialize all the subsystems that require initialization before threads start */
 void SDL_InitMainThread(void)
 {
-    if (SDL_main_thread_initialized) {
-        return;
-    }
-
     SDL_InitTLSData();
     SDL_InitTicks();
     SDL_InitFilesystem();
     SDL_InitLog();
     SDL_InitProperties();
     SDL_GetGlobalProperties();
-
-    SDL_main_thread_initialized = SDL_TRUE;
 }
 
 static void SDL_QuitMainThread(void)
 {
-    if (!SDL_main_thread_initialized) {
-        return;
-    }
-
     SDL_QuitProperties();
     SDL_QuitLog();
     SDL_QuitFilesystem();
     SDL_QuitTicks();
     SDL_QuitTLSData();
-
-    SDL_main_thread_initialized = SDL_FALSE;
 }
 
 int SDL_InitSubSystem(SDL_InitFlags flags)

src/SDL_log.c

@@ -118,6 +118,7 @@ void SDL_InitLog(void)
 void SDL_QuitLog(void)
 {
     SDL_ResetLogPriorities();
+
     if (log_function_mutex) {
         SDL_DestroyMutex(log_function_mutex);
         log_function_mutex = NULL;