Make ExportedObject and ObjectProxy own Bus as scoped_refptr.

dbus/bus.cc

Index: dbus/bus.cc
diff --git a/dbus/bus.cc b/dbus/bus.cc
index 843739ce9e218fc7f313c6536b12995a73eed6f0..fab372e56c8dde9e9d50fcd34c66ffdac2f1802c 100644
--- a/dbus/bus.cc
+++ b/dbus/bus.cc
@@ -293,6 +293,12 @@ void Bus::ShutdownAndBlock() {
     iter->second->Detach();
   }
 
+  // Release object proxies and exported objects here. We should do this
+  // here than in the destructor to avoid memory leaks due to cyclic
+  // reference.

[stevenjb, 2011/10/10 22:09:17]

nit: s/here than/here rather than/
nit: s/reference/references

[satorux1, 2011/10/11 17:24:33]

Done.

+  object_proxy_table_.clear();
+  exported_object_table_.clear();
+
   // Private connection should be closed.
   if (connection_) {
     if (connection_type_ == PRIVATE)