Make sure auth error reporting handles guest mode correctly.

chrome/browser/ui/views/profiles/profile_chooser_view.cc

 // Copyright 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/ui/views/profiles/profile_chooser_view.h"
 
 #include "base/prefs/pref_service.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
@@ skipping 79 matching lines @@
 }
 
 gfx::ImageSkia CreateSquarePlaceholderImage(int size) {
   SkBitmap bitmap;
   bitmap.setConfig(SkBitmap::kA8_Config, size, size);
   bitmap.allocPixels();
   bitmap.eraseARGB(0, 0, 0, 0);
   return gfx::ImageSkia::CreateFrom1xBitmap(bitmap);
 }
 
+// Note that guest mode profiles won't have a token service.
+const SigninErrorController* GetSigninErrorController(Profile* profile) {
+  const ProfileOAuth2TokenService* token_service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile);
+  return token_service ? token_service->signin_error_controller() : NULL;
+}
+
 bool HasAuthError(Profile* profile) {
-  SigninErrorController* error =
-      ProfileOAuth2TokenServiceFactory::GetForProfile(profile)->
-          signin_error_controller();
+  const SigninErrorController* error = GetSigninErrorController(profile);
   return error && error->HasError();
 }
 
 std::string GetAuthErrorAccountId(Profile* profile) {
-  SigninErrorController* error =
-      ProfileOAuth2TokenServiceFactory::GetForProfile(profile)->
-          signin_error_controller();
+  const SigninErrorController* error = GetSigninErrorController(profile);
   if (!error)
     return std::string();
 
   return error->error_account_id();
 }
 
 std::string GetAuthErrorUsername(Profile* profile) {
-  SigninErrorController* error =
-      ProfileOAuth2TokenServiceFactory::GetForProfile(profile)->
-          signin_error_controller();
+  const SigninErrorController* error = GetSigninErrorController(profile);
   if (!error)
     return std::string();
 
   return error->error_username();
 }
 
 // BackgroundColorHoverButton -------------------------------------------------
 
 // A custom button that allows for setting a background color when hovered over.
 class BackgroundColorHoverButton : public views::LabelButton {
@@ skipping 1270 matching lines @@
   layout->StartRowWithPadding(
       1, 0, 0, views::kUnrelatedControlVerticalSpacing);
   layout->AddView(end_preview_and_relaunch_button_);
 
   TitleCard* title_card = new TitleCard(
       IDS_PROFILES_END_PREVIEW, this, &end_preview_cancel_button_);
   return TitleCard::AddPaddedTitleCard(
       view, title_card, kFixedAccountRemovalViewWidth);
 }