Add a unified observer to replace NetworkManagerObserver

chrome/browser/chromeos/net/connectivity_state_helper_observer.h

Index: chrome/browser/chromeos/net/connectivity_state_helper_observer.h
diff --git a/chrome/browser/chromeos/net/connectivity_state_helper_observer.h b/chrome/browser/chromeos/net/connectivity_state_helper_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..4fe943e6808724fd09edc4d9b92f3818045a2837
--- /dev/null
+++ b/chrome/browser/chromeos/net/connectivity_state_helper_observer.h
@@ -0,0 +1,21 @@
+// Copyright (c) 2013 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 CHROME_BROWSER_CHROMEOS_NET_CONNECTIVITY_STATE_HELPER_OBSERVER_H_
+#define CHROME_BROWSER_CHROMEOS_NET_CONNECTIVITY_STATE_HELPER_OBSERVER_H_
+
+namespace chromeos {
+
+// A common observer interface used by the ConnectivityStateHelper object to
+// relay observing events received from the (older) NetworkLibrary or the (new)
+// NetworkStateHandler implementations.
+class ConnectivityStateHelperObserver {
+ public:
+  // Called when there's a change on the connection manager.
+  virtual void NetworkManagerChanged() = 0;

[stevenjb, 2013/03/11 23:11:05]

Call this ConnectivityChanged() instead? At some point we could also improve the
Helper to track the connected network and state, only triggering the callback
when connectivity actually changes.

[gauravsh, 2013/03/12 00:30:25]

This name matches the equivalent observer method in the
NetworkStateHandlerObserver. Perhaps we can change this to ConnectivityChanged()
once we use the NetworkStateHandler path by default.

Note that my eventual plan is to get rid of ConnectivityStateHelper* - this
interface is just so that we can make the transition easily instead of with a
single large CL.

+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_NET_CONNECTIVITY_STATE_HELPER_OBSERVER_H_