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

chrome/browser/metrics/chrome_metrics_services_manager_client.h

Index: chrome/browser/metrics/chrome_metrics_services_manager_client.h
diff --git a/chrome/browser/metrics/chrome_metrics_services_manager_client.h b/chrome/browser/metrics/chrome_metrics_services_manager_client.h
index d2b8ecaeb5fe568c04c20af5fef6ceda4985c1dd..1b8c92a17014452e1ea9d9f57324486c2f61dfd7 100644
--- a/chrome/browser/metrics/chrome_metrics_services_manager_client.h
+++ b/chrome/browser/metrics/chrome_metrics_services_manager_client.h
@@ -15,6 +15,7 @@
 class PrefService;
 
 namespace metrics {
+class EnabledStateProvider;
 class MetricsStateManager;
 }
 
@@ -26,6 +27,8 @@ class ChromeMetricsServicesManagerClient
   ~ChromeMetricsServicesManagerClient() override;
 
  private:
+  class ChromeEnabledStateProvider;

[Alexei Svitkine (slow), 2016/05/11 17:16:28]

Nit: Suggest making this a class in the anon namespace rather than a member
class. Since you use the interface for the member, no need to declare it in the
header.

[jwd, 2016/05/11 18:31:38]

I made it a member class to get access to
ChromeMetricsServiceAccessor::IsMetricsAndCrashReportingEnabled() through
ChromeMetricsServicesManagerClient's friendship. This seemed nicer than exposing
a public method on ChromeMetricsServicesManagerClient, and give
ChromeEnabledStateProvider a pointer to the ChromeMetricsServicesManagerClient
instance.

+
   // metrics_services_manager::MetricsServicesManagerClient:
   std::unique_ptr<rappor::RapporService> CreateRapporService() override;
   std::unique_ptr<variations::VariationsService> CreateVariationsService()
@@ -44,6 +47,10 @@ class ChromeMetricsServicesManagerClient
   // 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_;