ecore thread: Fix waiting.

Waiting would sometimes return as if the thread finished correctly while it is still running.

 This is because we’re waiting for the waiter data to be null… but this is always the case if the user-passed data is null!

 @fix

src/lib/ecore/ecore_thread.c

@@ -799,6 +799,7 @@ struct _Ecore_Thread_Waiter
    Ecore_Thread_Cb func_cancel;
    Ecore_Thread_Cb func_end;
    const void *data;
+   Eina_Bool waiting;
 };
 
 static void
@@ -808,10 +809,11 @@ _ecore_thread_wait_reset(Ecore_Thread_Waiter *waiter,
    worker->data = waiter->data;
    worker->func_cancel = waiter->func_cancel;
    worker->func_end = waiter->func_end;
-   // The waiter will be checked by _wait, NULL meaning it is done
+
    waiter->func_end = NULL;
    waiter->func_cancel = NULL;
    waiter->data = NULL;
+   waiter->waiting = EINA_FALSE;
 }
 
 static void
@@ -845,12 +847,13 @@ ecore_thread_wait(Ecore_Thread *thread, double wait)
    waiter.data = worker->data;
    waiter.func_end = worker->func_end;
    waiter.func_cancel = worker->func_cancel;
+   waiter.waiting = EINA_TRUE;
    // Now trick the thread to call the wrapper function
    worker->data = &waiter;
    worker->func_cancel = _ecore_thread_wait_cancel;
    worker->func_end = _ecore_thread_wait_end;
 
-   while (waiter.data)
+   while (waiter.waiting == EINA_TRUE)
      {
         double start, end;
 
@@ -863,7 +866,7 @@ ecore_thread_wait(Ecore_Thread *thread, double wait)
         if (wait <= 0) break;
      }
 
-   if (!waiter.data)
+   if (waiter.waiting == EINA_FALSE)
      {
         return EINA_TRUE;
      }