Add deletion observer to P2PSocketDispatcher.

content/renderer/p2p/socket_dispatcher.cc

Index: content/renderer/p2p/socket_dispatcher.cc
diff --git a/content/renderer/p2p/socket_dispatcher.cc b/content/renderer/p2p/socket_dispatcher.cc
index 4317725b7af9e753fde2dabca79db4daa7acdbc0..1b46dcb6de924d7a2658a4e8ab052a3d1a143ee9 100644
--- a/content/renderer/p2p/socket_dispatcher.cc
+++ b/content/renderer/p2p/socket_dispatcher.cc
@@ -59,6 +59,8 @@ P2PSocketDispatcher::P2PSocketDispatcher(RenderViewImpl* render_view)
 }
 
 P2PSocketDispatcher::~P2PSocketDispatcher() {
+  FOR_EACH_OBSERVER(P2PSocketDispatcherDestructionObserver,
+                    destruction_observer_, OnSocketDispatcherDestroyed());
   network_list_observers_->AssertEmpty();
   if (network_notifications_started_)
     Send(new P2PHostMsg_StopNetworkNotifications(routing_id()));
@@ -82,6 +84,16 @@ void P2PSocketDispatcher::RemoveNetworkListObserver(
   network_list_observers_->RemoveObserver(network_list_observer);
 }
 
+void P2PSocketDispatcher::AddDestructionObserver(
+    P2PSocketDispatcherDestructionObserver* observer) {
+  destruction_observer_.AddObserver(observer);
+}
+
+void P2PSocketDispatcher::RemoveDestructionObserver(
+    P2PSocketDispatcherDestructionObserver* observer) {
+  destruction_observer_.RemoveObserver(observer);
+}
+
 bool P2PSocketDispatcher::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(P2PSocketDispatcher, message)