ServiceWorker: Enable UseCounter for ServiceWorkerGlobalScope

content/browser/service_worker/service_worker_version.h

 // Copyright 2013 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 CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_VERSION_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_VERSION_H_
 
 #include <stdint.h>
 
 #include <functional>
@@ skipping 448 matching lines @@
   //       methods always return a rejected promise. And FetchEvent's
   //       preloadResponse attribute returns a promise which always resolve with
   //       undefined.
   //  - C: Navigation Preload related methods and attributes are not available
   //       in JS.
   // This method returns SUPPORTED only for A case.
   // blink::OriginTrials::serviceWorkerNavigationPreloadEnabled() returns true
   // 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) {
+    used_features_ = used_features;
+  }
+  std::set<uint32_t> used_features() const { return used_features_; }
+
  private:
   friend class base::RefCounted<ServiceWorkerVersion>;
   friend class ServiceWorkerMetrics;
   friend class ServiceWorkerReadFromCacheJobTest;
   friend class ServiceWorkerStallInStoppingTest;
   friend class ServiceWorkerURLRequestJobTest;
   friend class ServiceWorkerVersionBrowserTest;
   friend class ServiceWorkerVersionTest;
 
   FRIEND_TEST_ALL_PREFIXES(ServiceWorkerControlleeRequestHandlerTest,
@@ skipping 358 matching lines @@
   // while this service worker is running (i.e., after it starts up until it
   // stops).
   std::unique_ptr<ServiceWorkerMetrics::ScopedEventRecorder> event_recorder_;
 
   bool stop_when_devtools_detached_ = false;
 
   // Keeps the first purpose of starting the worker for UMA. Cleared in
   // FinishStartWorker().
   base::Optional<ServiceWorkerMetrics::EventType> start_worker_first_purpose_;
 
+  // This is the set of features that this worker has used. The values must be
+  // from blink::UseCounter::Feature enum.

[falken, 2017/02/08 05:01:53]

Can we mention this is the used features that were (1) used up until
installation of this version completed, or (2) used during the lifetime of
|this|.

If that's correct?

[nhiroki, 2017/02/09 05:11:32]

That's correct. Updated.

+  std::set<uint32_t> used_features_;
+
   base::WeakPtrFactory<ServiceWorkerVersion> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerVersion);
 };
 
 template <typename ResponseMessage>
 void ServiceWorkerVersion::DispatchSimpleEvent(int request_id,
                                                const IPC::Message& message) {
   RegisterSimpleRequest<ResponseMessage>(request_id);
   DispatchEvent({request_id}, message);
@@ skipping 38 matching lines @@
 
   // At this point |this| can have been deleted, so don't do anything other
   // than returning.
 
   return true;
 }
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_VERSION_H_