Added ClientEvent proto and structure for storing events in the factory.

google_apis/gcm/engine/connection_event_tracker.h

Index: google_apis/gcm/engine/connection_event_tracker.h
diff --git a/google_apis/gcm/engine/connection_event_tracker.h b/google_apis/gcm/engine/connection_event_tracker.h
new file mode 100644
index 0000000000000000000000000000000000000000..d52c99964421310d78cd2b7d1edaa0749ce40087
--- /dev/null
+++ b/google_apis/gcm/engine/connection_event_tracker.h
@@ -0,0 +1,69 @@
+// Copyright 2016 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 GOOGLE_APIS_GCM_ENGINE_CONNECTION_EVENT_TRACKER_H_
+#define GOOGLE_APIS_GCM_ENGINE_CONNECTION_EVENT_TRACKER_H_
+
+#include <deque>
+
+#include "google_apis/gcm/base/gcm_export.h"
+#include "google_apis/gcm/protocol/mcs.pb.h"
+#include "net/base/net_errors.h"
+#include "net/base/network_change_notifier.h"
+
+namespace mcs_proto {
+class LoginRequest;
+}
+
+namespace gcm {
+
+class GCM_EXPORT ConnectionEventTracker {
+ public:
+  // TODO(harkness): Pass in the storage information.
+  ConnectionEventTracker();
+  ~ConnectionEventTracker();
+
+  // Start recording a new connection attempt. This should never be called if
+  // a connection attempt is already ongoing.
+  void StartConnectionAttempt();
+
+  // Ends the record for a connection attempt and moves it to the completed
+  // connections list.
+  void EndConnectionAttempt();
+
+  // Record that the existing connection attempt has succeeded. Note that this
+  // doesn't mean the connection is necessarily valid. It could still fail with
+  // an authentication error.
+  void ConnectionAttemptSucceeded();
+
+  // Records that the connection succeeded but then failed to login.
+  void ConnectionLoginFailed();
+
+  // Record that the existing connection attempt has failed.
+  void ConnectionAttemptFailed(int error);
+
+  // Records the current type of network connection.

[Peter Beverloo, 2016/12/02 15:19:13]

micro nit:
  // To be called when the network connectivity changes.

(I don't think "Records" is completely appropriate.) Or just remove altogether.
I don't think either is particularly valuable.

[harkness, 2016/12/05 15:39:00]

Removing entirely as Nicolas referred me to a method I can use on demand
instead.

+  void OnNetworkChanged(

[Nicolas Zea, 2016/12/01 18:51:49]

nit: Only simple accessors should be inlined (and in that case named with
unix_hacker_style). Prefer out-of-lining this method.

[harkness, 2016/12/05 15:39:00]

Removing entirely.

+      net::NetworkChangeNotifier::ConnectionType network_type) {
+    network_type_ = network_type;
+  }
+
+  // Write any previous connection information to the login request.

[Peter Beverloo, 2016/12/02 15:19:13]

nit:
  ... information to the |*login_request|.

and rename the argument to login_request

[harkness, 2016/12/05 15:39:00]

Done.

+  void WriteToLoginRequest(mcs_proto::LoginRequest* request);
+
+ private:
+  // Storage for all the events which have completed.
+  std::deque<mcs_proto::ClientEvent> completed_events_;
+
+  // Current connection attempt.
+  mcs_proto::ClientEvent current_event_;
+
+  // The type of network connection when last updated.
+  net::NetworkChangeNotifier::ConnectionType network_type_ =
+      net::NetworkChangeNotifier::CONNECTION_NONE;
+};

[Peter Beverloo, 2016/12/02 15:19:13]

DISALLOW_COPY_AND_ASSIGN

[harkness, 2016/12/05 15:39:00]

Done.

+
+}  // namespace gcm
+
+#endif  // GOOGLE_APIS_GCM_ENGINE_CONNECTION_EVENT_TRACKER_H_