Fix potential crashes in NetworkHandler code

chromeos/network/auto_connect_handler.cc

Index: chromeos/network/auto_connect_handler.cc
diff --git a/chromeos/network/auto_connect_handler.cc b/chromeos/network/auto_connect_handler.cc
index b44478936775f27282fa1a76c89fb02d64a177e5..4411b18e0914e9bac770ab6164a91434a9733bb7 100644
--- a/chromeos/network/auto_connect_handler.cc
+++ b/chromeos/network/auto_connect_handler.cc
@@ -37,10 +37,12 @@ AutoConnectHandler::AutoConnectHandler()
 }
 
 AutoConnectHandler::~AutoConnectHandler() {
-  if (client_cert_resolver_)
-    client_cert_resolver_->RemoveObserver(this);
   if (LoginState::IsInitialized())
     LoginState::Get()->RemoveObserver(this);
+  if (client_cert_resolver_)
+    client_cert_resolver_->RemoveObserver(this);
+  if (network_connection_handler_)
+    network_connection_handler_->RemoveObserver(this);
   if (network_state_handler_)
     network_state_handler_->RemoveObserver(this, FROM_HERE);
   if (managed_configuration_handler_)