[sync] Hide "Sync nothing" UI; Go back to signing out on dashboard clears and abandoned initial set…

chrome/browser/sync/profile_sync_service.cc

 // Copyright (c) 2012 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 <cstddef>
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 1273 matching lines @@
         expect_sync_configuration_aborted_ = true;
       }
       // Trigger an unrecoverable error to stop syncing.
       OnInternalUnrecoverableError(FROM_HERE,
                                    last_actionable_error_.error_description,
                                    true,
                                    ERROR_REASON_ACTIONABLE_ERROR);
       break;
     case syncer::DISABLE_SYNC_ON_CLIENT:
       OnStopSyncingPermanently();
-      // TODO(rsimha): Re-evaluate whether to also sign out the user here after
-      // a dashboard clear. See http://crbug.com/240436.
+#if !defined(OS_CHROMEOS)
+      // On desktop Chrome, sign out the user after a dashboard clear.
+      // TODO(rsimha): Revisit this for M30. See http://crbug.com/252049.
+      if (!auto_start_enabled_)  // Skip sign out on ChromeOS/Android.
+        SigninManagerFactory::GetForProfile(profile_)->SignOut();
+#endif
       break;
     case syncer::STOP_SYNC_FOR_DISABLED_ACCOUNT:
       // Sync disabled by domain admin. we should stop syncing until next
       // restart.
       sync_disabled_by_admin_ = true;
       ShutdownImpl(true);
       break;
     default:
       NOTREACHED();
   }
@@ skipping 889 matching lines @@
 std::string ProfileSyncService::GetEffectiveUsername() {
 #if defined(ENABLE_MANAGED_USERS)
   if (ManagedUserService::ProfileIsManaged(profile_)) {
     DCHECK_EQ(std::string(), signin_->GetAuthenticatedUsername());
     return ManagedUserService::GetManagedUserPseudoEmail();
   }
 #endif
 
   return signin_->GetAuthenticatedUsername();
 }