Add BackupRollbackController for starting backup/rollback

chrome/browser/sync/backup_rollback_controller.cc

Index: chrome/browser/sync/backup_rollback_controller.cc
diff --git a/chrome/browser/sync/backup_rollback_controller.cc b/chrome/browser/sync/backup_rollback_controller.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8fb339c8e69dfc611c19790fe223e019068123df
--- /dev/null
+++ b/chrome/browser/sync/backup_rollback_controller.cc
@@ -0,0 +1,83 @@
+// Copyright (c) 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 "chrome/browser/sync/backup_rollback_controller.h"
+
+#include "base/command_line.h"
+#include "base/message_loop/message_loop.h"
+#include "chrome/browser/sync/managed_user_signin_manager_wrapper.h"
+#include "chrome/common/chrome_switches.h"
+#include "components/sync_driver/sync_prefs.h"
+
+namespace browser_sync {
+
+#if defined(OS_WIN) || defined(OS_LINUX) || defined(OS_MACOSX)
+// Number of rollback attempts to try before giving up.
+static const int kRollbackLimits = 3;
+#endif
+
+BackupRollbackController::BackupRollbackController(
+    sync_driver::SyncPrefs* sync_prefs,
+    const ManagedUserSigninManagerWrapper* signin,
+    base::Closure start_backup,
+    base::Closure start_rollback)
+    : sync_prefs_(sync_prefs),
+      signin_(signin),
+      start_backup_(start_backup),
+      start_rollback_(start_rollback),
+      weak_ptr_factory_(this) {
+}
+
+BackupRollbackController::~BackupRollbackController() {
+}
+
+void BackupRollbackController::Start(base::TimeDelta delay) {
+#if defined(OS_WIN) || defined(OS_LINUX) || defined(OS_MACOSX)
+  if (!CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kSyncEnableBackupRollback)) {
+    return;
+  }
+
+  if (delay == base::TimeDelta()) {
+    TryStart();
+  } else {
+    base::MessageLoop::current()->PostDelayedTask(
+        FROM_HERE,
+        base::Bind(&BackupRollbackController::TryStart,
+                   weak_ptr_factory_.GetWeakPtr()),
+        delay);
+  }
+#endif
+}
+
+void BackupRollbackController::OnRollbackReceived() {
+#if defined(OS_WIN) || defined(OS_LINUX) || defined(OS_MACOSX)
+  sync_prefs_->SetRemainingRollbackTries(kRollbackLimits);
+#endif
+}
+
+void BackupRollbackController::OnRollbackDone() {
+#if defined(OS_WIN) || defined(OS_LINUX) || defined(OS_MACOSX)
+  sync_prefs_->SetRemainingRollbackTries(0);
+#endif
+}
+
+void BackupRollbackController::TryStart() {
+  if (!signin_->GetEffectiveUsername().empty()) {
+    DVLOG(1) << "Don't start backup/rollback when user is signed in.";
+    return;
+  }
+
+  int rollback_tries = sync_prefs_->GetRemainingRollbackTries();
+  if (rollback_tries > 0) {
+    DVLOG(1) << "Start rollback.";
+    sync_prefs_->SetRemainingRollbackTries(rollback_tries - 1);
+    start_rollback_.Run();
+  } else {
+    DVLOG(1) << "Start backup.";
+    start_backup_.Run();
+  }
+}
+
+}  // namespace browser_sync