sync: don't allow NULL profile in ProfileSyncService and friends

chrome/browser/invalidation/invalidator_storage.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.
 //
 // Wraps PrefService in an InvalidationStateTracker to allow SyncNotifiers
 // to use PrefService as persistence for invalidation state. It is not thread
 // safe, and lives on the UI thread.
 
 #ifndef CHROME_BROWSER_INVALIDATION_INVALIDATOR_STORAGE_H_
 #define CHROME_BROWSER_INVALIDATION_INVALIDATOR_STORAGE_H_
@@ skipping 15 matching lines @@
 class PrefRegistrySyncable;
 }
 
 namespace invalidation {
 
 class InvalidatorStorage : public base::SupportsWeakPtr<InvalidatorStorage>,
                            public syncer::InvalidationStateTracker {
  public:
   static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
 
-  // |pref_service| may be NULL (for unit tests), but in that case no setter
-  // methods should be called. Does not own |pref_service|.
+  // |pref_service| may not be NULL. Does not own |pref_service|.
   explicit InvalidatorStorage(PrefService* pref_service);
   virtual ~InvalidatorStorage();
 
   // InvalidationStateTracker implementation.
   virtual syncer::InvalidationStateMap GetAllInvalidationStates() const
       OVERRIDE;
   virtual void SetMaxVersionAndPayload(const invalidation::ObjectId& id,
                                        int64 max_version,
                                        const std::string& payload) OVERRIDE;
   virtual void Forget(const syncer::ObjectIdSet& ids) OVERRIDE;
@@ skipping 38 matching lines @@
   static void SerializeToList(
       const syncer::InvalidationStateMap& state_map,
       base::ListValue* state_map_list);
 
   // Code for migrating from old MaxInvalidationVersions pref, which was a map
   // from sync types to max invalidation versions.
   void MigrateMaxInvalidationVersionsPref();
   static void DeserializeMap(const base::DictionaryValue* max_versions_dict,
                              syncer::InvalidationStateMap* map);
 
-  // May be NULL.
   PrefService* const pref_service_;
 
   DISALLOW_COPY_AND_ASSIGN(InvalidatorStorage);
 };
 
 }  // namespace invalidation
 
 #endif  // CHROME_BROWSER_INVALIDATION_INVALIDATOR_STORAGE_H_