sync: centralize sync startup decisions in TryStart.

chrome/browser/ui/webui/sync_setup_handler.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/ui/webui/sync_setup_handler.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
@@ skipping 996 matching lines @@
       } else {
         ProfileSyncService::SyncEvent(
             ProfileSyncService::CANCEL_FROM_SIGNON_WITHOUT_AUTH);
       }
     }
     // Let the various services know that we're no longer active.
     GetLoginUIService()->LoginUIClosed(this);
   }
 
   if (sync_service) {
-    sync_service->SetSetupInProgress(false);
-
     // Make sure user isn't left half-logged-in (signed in, but without sync
     // started up). If the user hasn't finished setting up sync, then sign out
     // and shut down sync.
     if (!sync_service->HasSyncSetupCompleted()) {
       DVLOG(1) << "Signin aborted by user action";
       sync_service->DisableForUser();
 
       browser_sync::SyncPrefs sync_prefs(GetProfile()->GetPrefs());
       sync_prefs.SetStartSuppressed(true);
     }
+    sync_service->SetSetupInProgress(false);
   }
 
   // Reset the attempted email address and error, otherwise the sync setup
   // overlay in the settings page will stay in whatever error state it was last
   // when it is reopened.
   last_attempted_user_email_.clear();
   last_signin_error_ = GoogleServiceAuthError::None();
 
   configuring_sync_ = false;
   signin_tracker_.reset();
@@ skipping 13 matching lines @@
   // 2) Normal signin through options page (IsSyncEnabledAndLoggedIn() will
   //    return false).
   // 3) Previously working credentials have expired
   //    (service->GetAuthError() != NONE).
   // 4) User is already signed in, but App Notifications needs to force another
   //    login so it can fetch an oauth token (passes force_login=true)
   // 5) User clicks [Advanced Settings] button on options page while already
   //    logged in.
   // 6) One-click signin (credentials are already available, so should display
   //    sync configure UI, not login UI).
+  // 7) ChromeOS re-enable after disabling sync.
   if (force_login ||
       !service->IsSyncEnabledAndLoggedIn() ||
       service->GetAuthError().state() != GoogleServiceAuthError::NONE) {
     // User is not logged in, or login has been specially requested - need to
     // display login UI (cases 1-4).
     DisplayGaiaLogin(false);
   } else {
     // User is already logged in. They must have brought up the config wizard
-    // via the "Advanced..." button or through One-Click signin (cases 5/6).
+    // via the "Advanced..." button or through One-Click signin (cases 5/6), or
+    // they are re-enabling sync on Chrome OS.
     DisplayConfigureSync(true, false);
   }
 
   if (!UseWebBasedSigninFlow())
     ShowSetupUI();
 }
 
 void SyncSetupHandler::OpenConfigureSync() {
   if (!PrepareSyncSetup())
     return;
@@ skipping 63 matching lines @@
     if (i != current_profile_index && AreUserNamesEqual(
         cache.GetUserNameOfProfileAtIndex(i), username_utf16)) {
       *error_message = l10n_util::GetStringUTF16(
           IDS_SYNC_USER_NAME_IN_USE_ERROR);
       return false;
     }
   }
 
   return true;
 }