Thread.Queue [Paranoia]: Broadcast the changed state.

This is intended to ensure that the state-changed signal
is not lost.

Consider the case when there is a thread that listens on the
condition, but does not act on it; it could starve the threads
that do intend to act on it.

Fixes [PIKE-140].

lib/modules/Thread.pmod

@@ -378,7 +378,7 @@ optional class Queue {
     buffer[w_ptr] = value;
     w_ptr++;
     int items = w_ptr - r_ptr;
-    r_cond::signal();
+    r_cond::broadcast();
     key=0;
     return items;
   }