Add a SigninAllowed policy.

chrome/browser/profiles/profile_io_data.h

 // 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.
 
 #ifndef CHROME_BROWSER_PROFILES_PROFILE_IO_DATA_H_
 #define CHROME_BROWSER_PROFILES_PROFILE_IO_DATA_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 157 matching lines @@
   }
 
   BooleanPrefMember* printing_enabled() const {
     return &printing_enabled_;
   }
 
   BooleanPrefMember* sync_disabled() const {
     return &sync_disabled_;
   }
 
+  BooleanPrefMember* signin_allowed() const {
+    return &signin_allowed_;
+  }
+
   net::TransportSecurityState* transport_security_state() const {
     return transport_security_state_.get();
   }
 
   bool is_incognito() const {
     return is_incognito_;
   }
 
   chrome_browser_net::ResourcePrefetchPredictorObserver*
       resource_prefetch_predictor_observer() const {
@@ skipping 294 matching lines @@
 
   mutable StringListPrefMember one_click_signin_rejected_email_list_;
 
   // Member variables which are pointed to by the various context objects.
   mutable BooleanPrefMember enable_referrers_;
   mutable BooleanPrefMember enable_do_not_track_;
   mutable BooleanPrefMember force_safesearch_;
   mutable BooleanPrefMember safe_browsing_enabled_;
   mutable BooleanPrefMember printing_enabled_;
   mutable BooleanPrefMember sync_disabled_;
+  mutable BooleanPrefMember signin_allowed_;
   // TODO(marja): Remove session_startup_pref_ if no longer needed.
   mutable IntegerPrefMember session_startup_pref_;
 
   // The state of metrics reporting in the browser that this profile runs on.
   // Unfortunately, since ChromeOS has a separate representation of this state,
   // we need to make one available based on the platform.
 #if defined(OS_CHROMEOS)
   bool enable_metrics_;
 #else
   BooleanPrefMember enable_metrics_;
@@ skipping 46 matching lines @@
 
   // TODO(jhawkins): Remove once crbug.com/102004 is fixed.
   bool initialized_on_UI_thread_;
 
   bool is_incognito_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileIOData);
 };
 
 #endif  // CHROME_BROWSER_PROFILES_PROFILE_IO_DATA_H_