[GCM] Adding GCMAccountMapper to link signed in profile to accounts.

components/gcm_driver/gcm_account_mapper.h

Index: components/gcm_driver/gcm_account_mapper.h
diff --git a/components/gcm_driver/gcm_account_mapper.h b/components/gcm_driver/gcm_account_mapper.h
new file mode 100644
index 0000000000000000000000000000000000000000..812a0a12eb1a3a2233217bc72ec8e5a9c573eed8
--- /dev/null
+++ b/components/gcm_driver/gcm_account_mapper.h
@@ -0,0 +1,116 @@
+// 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 COMPONENTS_GCM_DRIVER_GCM_ACCOUNT_MAPPER_H_
+#define COMPONENTS_GCM_DRIVER_GCM_ACCOUNT_MAPPER_H_
+
+#include <string>
+#include <vector>
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "components/gcm_driver/gcm_app_handler.h"
+#include "components/gcm_driver/gcm_client.h"
+#include "google_apis/gcm/engine/account_mapping.h"
+
+namespace base {
+class Clock;
+}
+
+namespace gcm {
+
+class GCMDriver;
+
+// Class for mapping signed in GAIA accounts to the GCM Device ID.

[jianli, 2014/08/28 18:43:52]

nit: signed-in

[fgorski, 2014/08/29 02:29:17]

Done.

+class GCMAccountMapper : public GCMAppHandler {
+ public:
+  // List of account mappings.
+  typedef std::vector<AccountMapping> AccountMappings;
+
+  explicit GCMAccountMapper(GCMDriver* gcm_driver);
+  virtual ~GCMAccountMapper();
+
+  // Initializes a list of mappings with |account_mappings| and sets the
+  // |registration_id| for the mapper, if it was previously registered with GCM.

[jianli, 2014/08/28 18:43:51]

Probably no need to comment since the method name and parameter names are clear
enough.

[fgorski, 2014/08/29 02:29:18]

Done.

+  void Initialize(const AccountMappings& account_mappings,
+                  const std::string& registration_id);
+
+  // Refreshes a list of accounts present in the system, providing them with
+  // corresponding access tokens.

[jianli, 2014/08/28 18:43:51]

Probably better to comment on when this is called, like:
  // Called when the account tokens are refreshed by AccountTracker. This
  // will cause the account mappings being refreshed and sent to the GCM.

[fgorski, 2014/08/29 02:29:18]

Done.

+  void SetAccountTokens(
+      const std::vector<GCMClient::AccountTokenInfo> account_tokens);
+
+  // Implementation of GCMAppHandler:
+  virtual void ShutdownHandler() OVERRIDE;
+  virtual void OnMessage(const std::string& app_id,
+                         const GCMClient::IncomingMessage& message) OVERRIDE;
+  virtual void OnMessagesDeleted(const std::string& app_id) OVERRIDE;
+  virtual void OnSendError(
+      const std::string& app_id,
+      const GCMClient::SendErrorDetails& send_error_details) OVERRIDE;
+  virtual void OnSendAcknowledged(const std::string& app_id,
+                                  const std::string& message_id) OVERRIDE;
+  virtual void OnConnected(const net::IPEndPoint& ip_endpoint) OVERRIDE;
+  virtual void OnDisconnected() OVERRIDE;
+  virtual bool CanHandle(const std::string& app_id) const OVERRIDE;
+
+ private:
+  friend class GCMAccountMapperTest;
+
+  typedef std::map<std::string, GCMClient::OutgoingMessage> OutgoingMessages;
+
+  // Sends a mapping message to GCM for the |account_mapping|.

[jianli, 2014/08/28 18:43:52]

Probably simpler to say:
  // Informs the GCM to add an account mapping.

[fgorski, 2014/08/29 02:29:18]

Done.

+  void SendAddMappingMessage(AccountMapping& account_mapping);
+
+  // Sends a message removing the mapping from GCM for the |account_mapping|.

[jianli, 2014/08/28 18:43:52]

ditto
  // Informs the GCM to remove an account mapping.

[fgorski, 2014/08/29 02:29:18]

Done.

+  void SendRemoveMappingMessage(AccountMapping& account_mapping);
+
+  // Callback for sending a message.
+  void OnSendFinished(const std::string& account_id,
+                      AccountMapping::MessageType message_type,
+                      const std::string& message_id,
+                      GCMClient::Result result);
+
+  // Checks whether the update can be triggered now, or if it is OK to wait
+  // until next time the token for account arrives.

[jianli, 2014/08/28 18:43:51]

The part before or and after or are contradicted.
  // Returns true if the GCM update can be triggered now. If the current time is
close
  // to the due time (within 6 hours), we want to trigger the update now to
inform
  // the server about the updated account mappings.

Also, it seems to be better to name IsUpdateDue as IsUpdateNeeded or
CanTriggerUpdate.

[fgorski, 2014/08/29 02:29:18]

Done.

+  bool IsUpdateDue(const base::Time& last_update_time) const;
+
+  // Checks whether last status change is older than a TTL of a message.
+  bool IsLastStatusChangeOlderThanTTL(
+      const base::Time& estimated_send_time) const;
+
+  // Finds an account mapping in |accounts_| by |account_id|.
+  AccountMapping* FindMappingByAccountId(const std::string& account_id);
+  // Finds an account mapping in |accounts_| by |message_id|.
+  // Returns iterator that can be used to delete the account.
+  AccountMappings::iterator FindMappingByMessageId(
+      const std::string& message_id);
+
+  // Sets the clock for testing.
+  void SetClockForTesting(scoped_ptr<base::Clock> clock);
+
+  // GCMDriver owns AccountMapper.

[jianli, 2014/08/28 18:43:52]

AccountMapper => GCMAccountMapper

[fgorski, 2014/08/29 02:29:18]

Done.

+  GCMDriver* gcm_driver_;
+
+  // Clock for timestamping status changes.
+  scoped_ptr<base::Clock> clock_;
+
+  // Currnetly tracked account mappings.
+  AccountMappings accounts_;
+
+  // GCM Registration ID of the account mapper.
+  std::string registration_id_;
+
+  // Is the account tracker initialized.

[jianli, 2014/08/28 18:43:52]

account tracker or mapper? Probably no need to add comment for this flag.

[fgorski, 2014/08/29 02:29:18]

Done.

+  bool initialized_;
+
+  base::WeakPtrFactory<GCMAccountMapper> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(GCMAccountMapper);
+};
+
+}  // namespace gcm
+
+#endif  // COMPONENTS_GCM_DRIVER_GCM_ACCOUNT_MAPPER_H_