ServiceWorker: Enable UseCounter for ServiceWorkerGlobalScope

content/browser/service_worker/service_worker_version.h

Index: content/browser/service_worker/service_worker_version.h
diff --git a/content/browser/service_worker/service_worker_version.h b/content/browser/service_worker/service_worker_version.h
index f8f95eff88a97be3d681e9a1bebfb4d35c49b5d9..1c3e2753fa56e00f8ba09e718e08440b69a5cce2 100644
--- a/content/browser/service_worker/service_worker_version.h
+++ b/content/browser/service_worker/service_worker_version.h
@@ -466,6 +466,12 @@ class CONTENT_EXPORT ServiceWorkerVersion
   // for both A and B case. So the methods and attributes are available in JS.
   NavigationPreloadSupportStatus GetNavigationPreloadSupportStatus() const;
 
+  void CountFeature(uint32_t feature);
+  void set_used_features(std::set<uint32_t> used_features) {

[dcheng, 2017/02/09 22:43:20]

Nit: Pass by const ref

[nhiroki, 2017/02/13 05:42:09]

Done.

+    used_features_ = used_features;
+  }
+  std::set<uint32_t> used_features() const { return used_features_; }

[dcheng, 2017/02/09 22:43:20]

Consider returning by const ref here as well.

[nhiroki, 2017/02/13 05:42:09]

Done.

+
  private:
   friend class base::RefCounted<ServiceWorkerVersion>;
   friend class ServiceWorkerMetrics;
@@ -844,6 +850,11 @@ class CONTENT_EXPORT ServiceWorkerVersion
   // FinishStartWorker().
   base::Optional<ServiceWorkerMetrics::EventType> start_worker_first_purpose_;
 
+  // This is the set of features that were used up until installation of this
+  // version completed, or used during the lifetime of |this|. The values must
+  // be from blink::UseCounter::Feature enum.
+  std::set<uint32_t> used_features_;
+
   base::WeakPtrFactory<ServiceWorkerVersion> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerVersion);