UKM Sync Observer

components/metrics_services_manager/metrics_services_manager.cc

Index: components/metrics_services_manager/metrics_services_manager.cc
diff --git a/components/metrics_services_manager/metrics_services_manager.cc b/components/metrics_services_manager/metrics_services_manager.cc
index e1ec65096b3e21b946d8fdb24bb489d1c3b6fc71..81c6b85866ef873cdfea5bdd006841de8930c431 100644
--- a/components/metrics_services_manager/metrics_services_manager.cc
+++ b/components/metrics_services_manager/metrics_services_manager.cc
@@ -68,14 +68,26 @@ void MetricsServicesManager::OnRendererProcessCrash() {
 metrics::MetricsServiceClient*
 MetricsServicesManager::GetMetricsServiceClient() {
   DCHECK(thread_checker_.CalledOnValidThread());
-  if (!metrics_service_client_)
+  if (!metrics_service_client_) {
     metrics_service_client_ = client_->CreateMetricsServiceClient();
+    // base::Unretained is safe since |this| owns the metrics_service_client_.
+    metrics_service_client_->SetUpdateRunningServicesCallback(
+        base::Bind(&MetricsServicesManager::UpdateRunningServices,
+                   base::Unretained(this)));
+  }
   return metrics_service_client_.get();
 }
 
 void MetricsServicesManager::UpdatePermissions(bool may_record,
                                                bool may_upload) {
   DCHECK(thread_checker_.CalledOnValidThread());
+  // If the user has opted out of metrics, delete local UKM state.
+  if (may_record_ && !may_record) {

[rkaplow, 2017/02/01 16:40:55]

nit - this just looks confusing. May want to rename the argument to
current_may_record or something. (and current_may_upload)

[Steven Holte, 2017/02/03 00:04:34]

Done.

+    ukm::UkmService* ukm = GetUkmService();
+    if (ukm)
+      ukm->Purge();
+  }
+
   // Stash the current permissions so that we can update the RapporServiceImpl
   // correctly when the Rappor preference changes.  The metrics recording
   // preference partially determines the initial rappor setting, and also
@@ -105,11 +117,8 @@ void MetricsServicesManager::UpdateRunningServices() {
 
     if (may_upload_) {
       metrics->EnableReporting();
-#if !defined(OFFICIAL_BUILD)
-      // TODO(holte): Make UKM check sync state instead of official build.
-      if (ukm)
+      if (ukm && metrics_service_client_->IsHistorySyncEnabledOnAllProfiles())
         ukm->EnableReporting();
-#endif
     } else {
       metrics->DisableReporting();
       if (ukm)