Add a SigninAllowed policy.

chrome/browser/profiles/profile.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.
 
 // This class gathers state related to a single user profile.
 
 #ifndef CHROME_BROWSER_PROFILES_PROFILE_H_
 #define CHROME_BROWSER_PROFILES_PROFILE_H_
 
 #include <string>
@@ skipping 333 matching lines @@
   }
 
   bool ShouldSendAccessibilityEvents() {
     return 0 == accessibility_pause_level_;
   }
 
   // Checks whether sync is configurable by the user. Returns false if sync is
   // disabled or controlled by configuration management.
   bool IsSyncAccessible();
 
+  // Checks whether signin to Chrome is allowed by the user. Returns false if
+  // signin is disabled or controlled by configuration management.
+  bool IsSigninAllowed();
+
   // Send NOTIFICATION_PROFILE_DESTROYED for this Profile, if it has not
   // already been sent. It is necessary because most Profiles are destroyed by
   // ProfileDestroyer, but in tests, some are not.
   void MaybeSendDestroyedNotification();
 
   // Creates an OffTheRecordProfile which points to this Profile.
   Profile* CreateOffTheRecordProfile();
 
  protected:
   // TODO(erg, willchan): Remove friendship once |ProfileIOData| is made into
@@ skipping 21 matching lines @@
 struct hash<Profile*> {
   std::size_t operator()(Profile* const& p) const {
     return reinterpret_cast<std::size_t>(p);
   }
 };
 
 }  // namespace BASE_HASH_NAMESPACE
 #endif
 
 #endif  // CHROME_BROWSER_PROFILES_PROFILE_H_