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

android_webview/browser/aw_metrics_service_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 ANDROID_WEBVIEW_BROWSER_AW_METRICS_SERVICE_CLIENT_IMPL_H_
 #define ANDROID_WEBVIEW_BROWSER_AW_METRICS_SERVICE_CLIENT_IMPL_H_
 
 #include <memory>
 #include <string>
 
 #include "android_webview/browser/aw_metrics_service_client.h"
 #include "base/lazy_instance.h"
 #include "base/macros.h"
+#include "components/metrics/enabled_state_provider.h"
 #include "components/metrics/metrics_service_client.h"
 
 class PrefService;
 
 namespace base {
 class FilePath;
 }
 
 namespace metrics {
 struct ClientInfo;
 class MetricsStateManager;
 }
 
 namespace net {
 class URLRequestContextGetter;
 }
 
 namespace android_webview {
 
 // This singleton manages metrics for an app using any number of WebViews. The
 // homonymous Java class is responsible for turning metrics on and off. This
 // singleton must always be used on the same thread. (Currently the UI thread
 // is enforced, but it could be any thread.) This is to prevent enable/disable
 // race conditions, and because MetricsService is single-threaded.
 // Initialization is asynchronous; even after Initialize has returned, some
 // methods may not be ready to use (see below).
-class AwMetricsServiceClient : public metrics::MetricsServiceClient {
+class AwMetricsServiceClient : public metrics::MetricsServiceClient,
+                               public metrics::EnabledStateProvider {
   friend struct base::DefaultLazyInstanceTraits<AwMetricsServiceClient>;
 
  public:
   // These may be called at any time.
   static AwMetricsServiceClient* GetInstance();
   void Initialize(PrefService* pref_service,
                   net::URLRequestContextGetter* request_context,
                   const base::FilePath guid_file_path);
   void SetMetricsEnabled(bool enabled);
 
   // These implement metrics::MetricsServiceClient. They must not be called
   // until initialization has asynchronously finished.
   metrics::MetricsService* GetMetricsService() override;
   void SetMetricsClientId(const std::string& client_id) override;
   void OnRecordingDisabled() override;
   bool IsOffTheRecordSessionActive() override;
   int32_t GetProduct() override;
   std::string GetApplicationLocale() override;
   bool GetBrand(std::string* brand_code) override;
   metrics::SystemProfileProto::Channel GetChannel() override;
   std::string GetVersionString() override;
   void OnLogUploadComplete() override;
   void InitializeSystemProfileMetrics(
       const base::Closure& done_callback) override;
   void CollectFinalMetricsForLog(const base::Closure& done_callback) override;
   std::unique_ptr<metrics::MetricsLogUploader> CreateUploader(
       const base::Callback<void(int)>& on_upload_complete) override;
   base::TimeDelta GetStandardUploadInterval() override;
 
+  // metrics::EnabledStateProvider implementation:

[Alexei Svitkine (slow), 2016/05/11 18:37:26]

Nit: New suggested syntax for these comments is just:

// metrics::EnableStateProvider:

[jwd, 2016/05/11 19:17:04]

Done.

+  bool IsConsentGiven() override;
+
  private:
   AwMetricsServiceClient();
   ~AwMetricsServiceClient() override;
 
   void InitializeWithGUID(std::string* guid);
 
-  // Callback for metrics::MetricsStateManager::Create
-  bool is_reporting_enabled();
-
   bool is_initialized_;
   bool is_enabled_;
   PrefService* pref_service_;
   net::URLRequestContextGetter* request_context_;
-  std::unique_ptr<metrics::MetricsStateManager> metrics_state_manager_;
   std::unique_ptr<metrics::MetricsService> metrics_service_;
+  std::unique_ptr<AwEnabledStateProvider> enabled_state_provider_;
 
   DISALLOW_COPY_AND_ASSIGN(AwMetricsServiceClient);
 };
 
 }  // namespace android_webview
 
 #endif  // ANDROID_WEBVIEW_BROWSER_AW_METRICS_SERVICE_CLIENT_IMPL_H_