Add new shill client for VPN

chromeos/dbus/shill_third_party_vpn_observer.h

Index: chromeos/dbus/shill_third_party_vpn_observer.h
diff --git a/chromeos/dbus/shill_third_party_vpn_observer.h b/chromeos/dbus/shill_third_party_vpn_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..f54b32c2c67c967b5ee60b192c7be30699cfeaaa
--- /dev/null
+++ b/chromeos/dbus/shill_third_party_vpn_observer.h
@@ -0,0 +1,28 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROMEOS_DBUS_SHILL_THIRD_PARTY_VPN_OBSERVER_H_
+#define CHROMEOS_DBUS_SHILL_THIRD_PARTY_VPN_OBSERVER_H_
+
+#include "base/basictypes.h"
+
+namespace chromeos {
+
+// This is a base class for observers which handle signals sent by the
+// ThirdPartyVpnAdaptor in Shill.
+class ShillThirdPartyVpnObserver {
+ public:
+  // Ownership of |data| belongs to the caller, hence the contents should be
+  // consumed before the call returns, i.e., pointer should not be dereferenced
+  // after the function returns.
+  virtual void OnPacketReceived(const uint8* data, size_t length) = 0;
+  virtual void OnPlatformMessage(uint32 connection_state) = 0;
+
+ protected:
+  virtual ~ShillThirdPartyVpnObserver() {}
+};
+
+}  // namespace chromeos
+
+#endif  // CHROMEOS_DBUS_SHILL_THIRD_PARTY_VPN_OBSERVER_H_