No longer trigger signin errors on connection_failed for sync.

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 422 matching lines @@
   if (!service->sync_initialized()) {
 
 #if !defined(OS_CHROMEOS)
     // When user tries to setup sync while the sync backend is not initialized,
     // kick the sync backend and wait for it to be ready and show spinner until
     // the backend gets ready.
     retry_on_signin_failure_ = false;
 #endif
 
     service->UnsuppressAndStart();
-    DisplaySpinner();
+
+    // See if it's even possible to bring up the sync backend - if not
+    // (unrecoverable error?), don't bother displaying a spinner that will be
+    // immediately closed because this leads to some ugly infinite UI loop (see
+    // http://crbug.com/244769).
+    if (SigninTracker::GetSigninState(GetProfile(), NULL) !=
+        SigninTracker::WAITING_FOR_GAIA_VALIDATION) {
+      DisplaySpinner();
+    }
 
     // To listen to the token available notifications, start SigninTracker.
     signin_tracker_.reset(
         new SigninTracker(GetProfile(),
                           this,
                           SigninTracker::SERVICES_INITIALIZING));
     return;
   }
 
   // Should only be called if user is signed in, so no longer need our
@@ skipping 924 matching lines @@
   return LoginUIServiceFactory::GetForProfile(GetProfile());
 }
 
 void SyncSetupHandler::CloseOverlay() {
   // Stop a timer to handle timeout in waiting for sync setup.
   backend_start_timer_.reset();
 
   CloseSyncSetup();
   web_ui()->CallJavascriptFunction("OptionsPage.closeOverlay");
 }