MAINT-5232: Make LLPounceable noncopyable.

Changing the queue-of-callables implementation to boost::signals2::signal,
which is noncopyable, means that LLPounceable itself should be noncopyable.

indra/llcommon/llpounceable.h

@@ -36,6 +36,7 @@
 #define LL_LLPOUNCEABLE_H
 
 #include "llsingleton.h"
+#include <boost/noncopyable.hpp>
 #include <boost/call_traits.hpp>
 #include <boost/type_traits/remove_pointer.hpp>
 #include <boost/utility/value_init.hpp>
@@ -137,7 +138,7 @@ private:
 // LLPounceable<T> is for an LLPounceable instance on the heap or the stack.
 // LLPounceable<T, LLPounceableStatic> is for a static LLPounceable instance.
 template <typename T, class TAG=LLPounceableQueue>
-class LLPounceable
+class LLPounceable: public boost::noncopyable
 {
 private:
     typedef LLPounceableTraits<T, TAG> traits;

indra/llcommon/tests/llpounceable_test.cpp

@@ -147,7 +147,7 @@ namespace tut
         Data a("a");
         // should be able to initialize a pounceable (when its constructor
         // runs)
-        LLPounceable<Data*> pounceable = &a;
+        LLPounceable<Data*> pounceable(&a);
         // should be able to pass LLPounceable<T> to function accepting T
         setter(&aptr, pounceable);
         ensure_equals("aptr should be &a", aptr, &a);