Simulate variation seeds using installed version string.

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"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "base/metrics/field_trial.h"
+#include "base/task_runner_util.h"

[Ilya Sherman, 2014/06/18 17:11:36]

nit: Does this need to be in the header file, or can it be moved to the
implementation file?

[Alexei Svitkine (slow), 2014/06/18 17:17:17]

Oops, meant to add it to the .cc file, but I guess I had the wrong file open.
Fixed now.

 #include "base/time/time.h"
 #include "chrome/browser/metrics/variations/variations_request_scheduler.h"
 #include "chrome/browser/metrics/variations/variations_seed_store.h"
 #include "chrome/browser/web_resource/resource_request_allowed_notifier.h"
 #include "chrome/common/chrome_version_info.h"
 #include "net/url_request/url_fetcher_delegate.h"
 #include "url/gurl.h"
 
 #if defined(OS_WIN)
 #include "chrome/browser/metrics/variations/variations_registry_syncer_win.h"
 #endif
 
 class PrefService;
 class PrefRegistrySimple;
 
-namespace user_prefs {
-class PrefRegistrySyncable;
+namespace base {
+class Version;
 }
 
 namespace metrics {
 class MetricsStateManager;
 }
 
+namespace user_prefs {
+class PrefRegistrySyncable;
+}
+
 namespace chrome_variations {
 
 class VariationsSeed;
 
 // 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:
@@ skipping 91 matching lines @@
   // 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;
 
+  // Performs a variations seed simulation with the given |seed| and |version|
+  // and logs the simulation results as histograms.
+  void PerformSimulationWithVersion(scoped_ptr<VariationsSeed> seed,
+                                    const base::Version& version);
+
   // Record the time of the most recent successful fetch.
   void RecordLastFetchTime();
 
   // The pref service used to store persist the variations seed.
   PrefService* local_state_;
 
   // Used for instantiating entropy providers for variations seed simulation.
   // Weak pointer.
   metrics::MetricsStateManager* state_manager_;
 
@@ skipping 28 matching lines @@
 
   // 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_;
 
 #if defined(OS_WIN)
   // Helper that handles synchronizing Variations with the Registry.
   VariationsRegistrySyncer registry_syncer_;
 #endif
 
+  base::WeakPtrFactory<VariationsService> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(VariationsService);
 };
 
 }  // namespace chrome_variations
 
 #endif  // CHROME_BROWSER_METRICS_VARIATIONS_VARIATIONS_SERVICE_H_