Enable the VariationsService on official builds when --variations-service-url is provided.

chrome/browser/metrics/variations/variations_service.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_METRICS_VARIATIONS_VARIATIONS_SERVICE_H_
 #define CHROME_BROWSER_METRICS_VARIATIONS_VARIATIONS_SERVICE_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
@@ skipping 13 matching lines @@
 class PrefServiceSimple;
 
 namespace chrome_variations {
 
 // Used to setup field trials based on stored variations seed data, and fetch
 // new seed data from the variations server.
 class VariationsService
     : public net::URLFetcherDelegate,
       public ResourceRequestAllowedNotifier::Observer {
  public:
-  VariationsService();
-
-  // This constructor exists for injecting a mock notifier. It is meant for
-  // testing only. This instance will take ownership of |notifier|.
-  explicit VariationsService(ResourceRequestAllowedNotifier* notifier);
-
   virtual ~VariationsService();
 
   // Creates field trials based on Variations Seed loaded from local prefs. If
   // there is a problem loading the seed data, all trials specified by the seed
   // may not be created.
   bool CreateTrialsFromSeed(PrefService* local_prefs);
 
   // Calls FetchVariationsSeed once and repeats this periodically. See
   // implementation for details on the period. Must be called after
   // |CreateTrialsFromSeed|.
   void StartRepeatedVariationsSeedFetch();
 
+  // Exposed for testing.
+  void SetCreateTrialsFromSeedCalledForTesting(bool called);

[Alexei Svitkine (slow), 2013/01/03 20:14:06]

Are you using this somewhere?

[SteveT, 2013/01/03 20:35:42]

I believe this is used by the tests. It was just moved around in this CL so
static methods are better grouped.

[Alexei Svitkine (slow), 2013/01/03 20:40:42]

Ah, I misread the diff before. SGTM.

+
   // Register Variations related prefs in Local State.
   static void RegisterPrefs(PrefServiceSimple* prefs);
 
-  // Exposed for testing.
-  void SetCreateTrialsFromSeedCalledForTesting(bool called);
+  // Factory method for creating a VariationsService.
+  static VariationsService* Create();
 
  protected:
   // Starts the fetching process once, where |OnURLFetchComplete| is called with
   // the response.
   virtual void DoActualFetch();
 
+  // This constructor exists for injecting a mock notifier. It is meant for
+  // testing only. This instance will take ownership of |notifier|.
+  explicit VariationsService(ResourceRequestAllowedNotifier* notifier);
+
  private:
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, CheckStudyChannel);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, CheckStudyLocale);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, CheckStudyPlatform);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, CheckStudyVersion);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, CheckStudyVersionWildcards);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, CheckStudyStartDate);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, DoNotFetchIfOffline);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, DoNotFetchIfOnlineToOnline);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, FetchOnReconnect);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, IsStudyExpired);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, LoadSeed);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, StoreSeed);
   FRIEND_TEST_ALL_PREFIXES(VariationsServiceTest, ValidateStudy);
 
+  // Default constructor is private. Use the |Create| factory method to create a
+  // VariationsService.
+  VariationsService();
+
   // Checks if prerequisites for fetching the Variations seed are met, and if
   // so, performs the actual fetch using |DoActualFetch|.
   void FetchVariationsSeed();
 
   // net::URLFetcherDelegate implementation:
   virtual void OnURLFetchComplete(const net::URLFetcher* source) OVERRIDE;
 
   // ResourceRequestAllowedNotifier::Observer implementation:
   virtual void OnResourceRequestsAllowed() OVERRIDE;
 
@@ skipping 76 matching lines @@
   scoped_ptr<ResourceRequestAllowedNotifier> resource_request_allowed_notifier_;
 
   // The start time of the last seed request. This is used to measure the
   // latency of seed requests. Initially zero.
   base::TimeTicks last_request_started_time_;
 };
 
 }  // namespace chrome_variations
 
 #endif  // CHROME_BROWSER_METRICS_VARIATIONS_VARIATIONS_SERVICE_H_