Add support for temporarily disabling sync.

chrome/browser/sync/profile_sync_service.cc

 // Copyright (c) 2011 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/profile_sync_service.h"
 
 #include <algorithm>
 #include <cstddef>
 #include <map>
 #include <set>
@@ skipping 170 matching lines @@
   // for the TokenService in login and does not normally rely on signin_,
   // so only initialize this if the token service has not been initialized
   // (e.g. the browser crashed or is being debugged).
   if (cros_user_.empty() ||
       !profile_->GetTokenService()->Initialized()) {
     // Will load tokens from DB and broadcast Token events after.
     // Note: We rely on signin_ != NULL unless !cros_user_.empty().
     signin_->Initialize(profile_);
   }
 
-  if (!HasSyncSetupCompleted()) {
-    // If autostart is enabled, but we haven't completed sync setup, try to
-    // start sync anyway (it's possible we crashed/shutdown after logging in
-    // but before the backend finished initializing the last time).
-    if (auto_start_enabled_ && !sync_prefs_.IsStartSuppressed() &&
-        AreCredentialsAvailable()) {
+  StartUpIfNotSuppressed();
+}
+
+void ProfileSyncService::StartUpIfNotSuppressed() {
+  if (!sync_prefs_.IsStartSuppressed() && AreCredentialsAvailable()) {
+    if (HasSyncSetupCompleted() || auto_start_enabled_) {
+      // If sync setup has completed we always start the backend.
+      // If autostart is enabled, but we haven't completed sync setup, we try to
+      // start sync anyway, since it's possible we crashed/shutdown after
+      // logging in but before the backend finished initializing the last time.
+      // Note that if we haven't finished setting up sync, backend bring up will
+      // be done by the wizard.
       StartUp();
     }
-  } else if (AreCredentialsAvailable()) {
-    // If we have credentials and sync setup finished, autostart the backend.
-    // Note that if we haven't finished setting up sync, backend bring up will
-    // be done by the wizard.
-    StartUp();
   }
 }
 
 void ProfileSyncService::RegisterAuthNotifications() {
   registrar_.Add(this,
                  chrome::NOTIFICATION_TOKEN_AVAILABLE,
                  content::Source<TokenService>(profile_->GetTokenService()));
   registrar_.Add(this,
                  chrome::NOTIFICATION_TOKEN_LOADING_FINISHED,
                  content::Source<TokenService>(profile_->GetTokenService()));
@@ skipping 1291 matching lines @@
   // another, and no unrecoverable error has transpired.
   if (unrecoverable_error_detected_)
     return false;
 
   if (!data_type_manager_.get())
     return false;
 
   return data_type_manager_->state() == DataTypeManager::CONFIGURED;
 }
 
+void ProfileSyncService::StopSyncAndSuppressStartUp() {
+  sync_prefs_.SetStartSuppressed(true);
+  Shutdown(false);
+}
+
+void ProfileSyncService::DisableSyncSuppressionAndStartUpSync() {
+  DCHECK(profile_);
+  sync_prefs_.SetStartSuppressed(false);
+  // Set username in SigninManager, as SigninManager::OnGetUserInfoSuccess
+  // is never called for some clients.
+  if (signin_->GetUsername().empty()) {
+    signin_->SetUsername(profile_->GetProfileName());

[akalin, 2011/10/26 18:53:09]

What is the username used for?  Isn't the profile name just some arbitrary name
(like "Profile0") and not related to the sync account?  If it's something
platform-specific maybe that should be mentioned, and/or this should be put in
an ifdef.

+  }
+  StartUpIfNotSuppressed();
+}
+
 void ProfileSyncService::AcknowledgeSyncedTypes() {
   syncable::ModelTypeSet registered_types;
   GetRegisteredDataTypes(&registered_types);
   sync_prefs_.AcknowledgeSyncedTypes(registered_types);
 }
 
 void ProfileSyncService::ReconfigureDatatypeManager() {
   // If we haven't initialized yet, don't configure the DTM as it could cause
   // association to start before a Directory has even been created.
   if (backend_initialized_) {
@@ skipping 11 matching lines @@
             << "Unrecoverable error.";
   } else {
     VLOG(0) << "ConfigureDataTypeManager not invoked because backend is not "
             << "initialized";
   }
 }
 
 const FailedDatatypesHandler& ProfileSyncService::failed_datatypes_handler() {
   return failed_datatypes_handler_;
 }