chromeos: Avoid EasyUnlockGetKeysOperation D-Bus log spam.

chrome/browser/chromeos/login/easy_unlock/easy_unlock_get_keys_operation.h

 // 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 CHROME_BROWSER_CHROMEOS_LOGIN_EASY_UNLOCK_EASY_UNLOCK_GET_KEYS_OPERATION_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_EASY_UNLOCK_EASY_UNLOCK_GET_KEYS_OPERATION_H_
 
 #include <stddef.h>
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/chromeos/login/easy_unlock/easy_unlock_types.h"
 #include "chromeos/cryptohome/homedir_methods.h"
 #include "chromeos/login/auth/user_context.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 
 namespace chromeos {
 
 class EasyUnlockGetKeysOperation {
  public:
   typedef base::Callback<void(bool success,
                               const EasyUnlockDeviceKeyDataList& data_list)>
       GetKeysCallback;
   EasyUnlockGetKeysOperation(const UserContext& user_context,
                              const GetKeysCallback& callback);
   ~EasyUnlockGetKeysOperation();
 
+  // Starts the operation. If the cryptohome service is not yet available, the
+  // request will be deferred until it is ready.
   void Start();
 
  private:
+  // Called once when the cryptohome service is available.
+  void OnCryptohomeAvailable(bool available);
+
+  // Asynchronously requests data for |key_index_| from cryptohome.
   void GetKeyData();
+
+  // Callback for GetKeyData(). Updates |devices_|, increments |key_index_|, and
+  // calls GetKeyData() again.
   void OnGetKeyData(
       bool success,
       cryptohome::MountError return_code,
       const std::vector<cryptohome::KeyDefinition>& key_definitions);
 
   UserContext user_context_;
   GetKeysCallback callback_;
 
   size_t key_index_;
   EasyUnlockDeviceKeyDataList devices_;
 
   base::WeakPtrFactory<EasyUnlockGetKeysOperation> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(EasyUnlockGetKeysOperation);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_EASY_UNLOCK_EASY_UNLOCK_GET_KEYS_OPERATION_H_