Clean up Smart Lock cryptohome keys logic:

chrome/browser/chromeos/login/easy_unlock/easy_unlock_refresh_keys_operation.cc

+// 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.
+
+#include "base/bind.h"
+#include "chrome/browser/chromeos/login/easy_unlock/easy_unlock_create_keys_operation.h"
+#include "chrome/browser/chromeos/login/easy_unlock/easy_unlock_refresh_keys_operation.h"
+#include "chrome/browser/chromeos/login/easy_unlock/easy_unlock_remove_keys_operation.h"
+
+namespace chromeos {
+
+EasyUnlockRefreshKeysOperation::EasyUnlockRefreshKeysOperation(
+    const UserContext& user_context,
+    const std::string& tpm_public_key,
+    const EasyUnlockDeviceKeyDataList& devices,
+    const RefreshKeysCallback& callback)
+    : user_context_(user_context),
+      tpm_public_key_(tpm_public_key),
+      devices_(devices),
+      callback_(callback),
+      weak_ptr_factory_(this) {
+}
+
+EasyUnlockRefreshKeysOperation::~EasyUnlockRefreshKeysOperation() {
+}
+
+void EasyUnlockRefreshKeysOperation::Start() {
+  if (devices_.empty()) {
+    OnKeysCreated(true);
+    return;
+  }
+
+  create_keys_operation_.reset(new EasyUnlockCreateKeysOperation(
+      user_context_, tpm_public_key_, devices_,
+      base::Bind(&EasyUnlockRefreshKeysOperation::OnKeysCreated,
+                 weak_ptr_factory_.GetWeakPtr())));
+  create_keys_operation_->Start();
+}
+
+void EasyUnlockRefreshKeysOperation::OnKeysCreated(bool success) {
+  if (!success) {
+    callback_.Run(false);
+    return;
+  }
+
+  // Update the user context to have the new authorization keys after the create
+  // keys operation.

[tbarzic, 2014/12/18 10:49:05]

you could mention reason for doing this (otherwise the comment seems a bit
redundant)

[Tim Song, 2014/12/18 22:42:54]

Done.

+  if (create_keys_operation_)
+    user_context_ = create_keys_operation_->user_context();
+
+  remove_keys_operation_.reset(new EasyUnlockRemoveKeysOperation(
+      user_context_, devices_.size(),
+      base::Bind(&EasyUnlockRefreshKeysOperation::OnKeysRemoved,
+                 weak_ptr_factory_.GetWeakPtr())));
+  remove_keys_operation_->Start();
+}
+
+void EasyUnlockRefreshKeysOperation::OnKeysRemoved(bool success) {
+  callback_.Run(success);
+}
+
+}  // namespace chromeos