Add some logging messages to winmm to ease debugging and make the logging test pass

src/cubeb_winmm.c

@@ -167,6 +167,8 @@ winmm_refill_stream(cubeb_stream * stm)
   long wanted;
   MMRESULT r;
 
+  ALOG("winmm_refill_stream");
+
   EnterCriticalSection(&stm->lock);
   stm->free_buffers += 1;
   XASSERT(stm->free_buffers > 0 && stm->free_buffers <= NBUFS);
@@ -174,6 +176,7 @@ winmm_refill_stream(cubeb_stream * stm)
   if (stm->draining) {
     LeaveCriticalSection(&stm->lock);
     if (stm->free_buffers == NBUFS) {
+      ALOG("winmm_refill_stream draining");
       stm->state_callback(stm, stm->user_ptr, CUBEB_STATE_DRAINED);
     }
     SetEvent(stm->event);
@@ -232,6 +235,8 @@ winmm_refill_stream(cubeb_stream * stm)
     return;
   }
 
+  ALOG("winmm_refill_stream %ld frames", got);
+
   LeaveCriticalSection(&stm->lock);
 }
 
@@ -575,6 +580,8 @@ winmm_stream_init(cubeb * context, cubeb_stream ** stream,
 
   *stream = stm;
 
+  LOG("winmm_stream_init OK");
+
   return CUBEB_OK;
 }