Splitting the concept of UMA consent, and should UMA report.

ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.h

 // Copyright 2015 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 IOS_CHROME_BROWSER_METRICS_IOS_CHROME_METRICS_SERVICES_MANAGER_CLIENT_H_
 #define IOS_CHROME_BROWSER_METRICS_IOS_CHROME_METRICS_SERVICES_MANAGER_CLIENT_H_
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/threading/thread_checker.h"
 #include "components/metrics_services_manager/metrics_services_manager_client.h"
 
 class PrefService;
 
 namespace metrics {
+class EnabledStateProvider;
 class MetricsStateManager;
 }
 
 // Provides an //ios/chrome-specific implementation of
 // MetricsServicesManagerClient.
 class IOSChromeMetricsServicesManagerClient
     : public metrics_services_manager::MetricsServicesManagerClient {
  public:
   explicit IOSChromeMetricsServicesManagerClient(PrefService* local_state);
   ~IOSChromeMetricsServicesManagerClient() override;
 
  private:
+  // This is defined as a member class to get access to
+  // IOSChromeMetricsServiceAccessor through
+  // IOSChromeMetricsServicesManagerClient's friendship.
+  class IOSChromeEnabledStateProvider;
+
   // metrics_services_manager::MetricsServicesManagerClient:
   std::unique_ptr<rappor::RapporService> CreateRapporService() override;
   std::unique_ptr<variations::VariationsService> CreateVariationsService()
       override;
   std::unique_ptr<metrics::MetricsServiceClient> CreateMetricsServiceClient()
       override;
   net::URLRequestContextGetter* GetURLRequestContext() override;
   bool IsSafeBrowsingEnabled(const base::Closure& on_update_callback) override;
   bool IsMetricsReportingEnabled() override;
   bool OnlyDoMetricsRecording() override;
 
   // Gets the MetricsStateManager, creating it if it has not already been
   // created.
   metrics::MetricsStateManager* GetMetricsStateManager();
 
   // MetricsStateManager which is passed as a parameter to service constructors.
   std::unique_ptr<metrics::MetricsStateManager> metrics_state_manager_;
 
+  // EnabledStateProvider to communicate if the client has consented to metrics
+  // reporting, and if it's enabled.
+  std::unique_ptr<metrics::EnabledStateProvider> enabled_state_provider_;
+
   // 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_;
 
   DISALLOW_COPY_AND_ASSIGN(IOSChromeMetricsServicesManagerClient);
 };
 
 #endif  // IOS_CHROME_BROWSER_METRICS_IOS_CHROME_METRICS_SERVICES_MANAGER_CLIENT_H_