Pass MetricsServiceClient into MetricsService, and create a simple stubbed TestMetricsServiceClient…

chrome/browser/metrics/metrics_services_manager.h

 // Copyright 2014 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_METRICS_SERVICES_MANAGER_H_
 #define CHROME_BROWSER_METRICS_METRICS_SERVICES_MANAGER_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/threading/thread_checker.h"
+#include "chrome/browser/metrics/chrome_metrics_service_client.h"
 
 class MetricsService;
 class PrefService;
 
 namespace metrics {
 class MetricsStateManager;
 }
 
 namespace rappor {
 class RapporService;
@@ skipping 26 matching lines @@
 
   // Ensures that all functions are called from the same thread.
   base::ThreadChecker thread_checker_;
 
   // Weak pointer to the local state prefs store.
   PrefService* local_state_;
 
   // MetricsStateManager which is passed as a parameter to service constructors.
   scoped_ptr<metrics::MetricsStateManager> metrics_state_manager_;
 
+  // Chrome embedder implementation of the MetricsServiceClient, which is passed
+  // as a parameter to the MetricsService.
+  ChromeMetricsServiceClient metrics_service_client_;
+
   // The MetricsService, used for UMA report uploads.
   scoped_ptr<MetricsService> metrics_service_;
 
   // The RapporService, for RAPPOR metric uploads.
   scoped_ptr<rappor::RapporService> rappor_service_;
 
   // The VariationsService, for server-side experiments infrastructure.
   scoped_ptr<chrome_variations::VariationsService> variations_service_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsServicesManager);
 };
 
 #endif  // CHROME_BROWSER_METRICS_METRICS_SERVICES_MANAGER_H_