Service Worker: Prepare for connecting Mojo for FetchEventWorkerTiming in worker

This patch is a part of FetchEvent WorkerTiming patches. This feature enables a
service worker to attach PerformanceMark/PerformanceMeasure timings to a
request during the fetch event handler. The timings will then be exposed to the
page using blink::PerformanceResourceTiming.

This patch prepares for passing a Mojo pending receiver for
WorkerTimingContainer to blink::PerformanceResourceTiming. In order to identify
a Mojo receiver corresponding to a FetchEvent, WebWorkerFetchContextImpl has
a map from |request_id| to a pending receiver. This patch adds a method to take
a Mojo pending receiver from content::WebWorkerFetchContextImpl. It's used to
pass Mojo pending receivers to blink::PerformanceResourceTiming in later
patches.

Explainer : https://github.com/wanderview/fetchevent-worker-timing/blob/master/explainer.md
Design doc: https://docs.google.com/document/d/1-ebnv7OFiVd3k2-jbtQGO5s3BKHIp7lRx3ujhgNKvB0

Bug: 900700
Change-Id: I3d1119362b2eabbce4df1d709f392a87ba42cc18
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1924343
Commit-Queue: Yuta Kasai <yutakasai@google.com>
Reviewed-by: Hiroki Nakagawa <nhiroki@chromium.org>
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#719077}

content/renderer/loader/web_worker_fetch_context_impl.cc

@@ -524,6 +524,17 @@ WebWorkerFetchContextImpl::CreateWebSocketHandshakeThrottle(
       ancestor_frame_id_, std::move(task_runner));
 }
 
+mojo::ScopedMessagePipeHandle
+WebWorkerFetchContextImpl::TakePendingWorkerTimingReceiver(int request_id) {
+  auto iter = worker_timing_container_receivers_.find(request_id);
+  if (iter == worker_timing_container_receivers_.end()) {
+    return {};
+  }
+  auto receiver = std::move(iter->second);
+  worker_timing_container_receivers_.erase(iter);
+  return receiver.PassPipe();
+}
+
 void WebWorkerFetchContextImpl::set_controller_service_worker_mode(
     blink::mojom::ControllerServiceWorkerMode mode) {
   controller_service_worker_mode_ = mode;
@@ -633,9 +644,6 @@ void WebWorkerFetchContextImpl::ResetServiceWorkerURLLoaderFactory() {
        base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN});
   auto current_task_runner =
       base::CreateSequencedTaskRunner({base::CurrentThread()});
-  // TODO(https://crbug.com/900700): Pass RepeatingCallback to store
-  // WorkerTimingContainer pending receiver and request_id from
-  // ServiceWorkerSubresourceLoaderFactory.
   task_runner->PostTask(
       FROM_HERE,
       base::BindOnce(
@@ -643,7 +651,10 @@ void WebWorkerFetchContextImpl::ResetServiceWorkerURLLoaderFactory() {
           std::move(service_worker_container_host), client_id_,
           fallback_factory_->Clone(),
           service_worker_url_loader_factory.InitWithNewPipeAndPassReceiver(),
-          task_runner, std::move(current_task_runner), base::DoNothing()));
+          task_runner, std::move(current_task_runner),
+          base::BindRepeating(
+              &WebWorkerFetchContextImpl::AddPendingWorkerTimingReceiver,
+              weak_factory_.GetWeakPtr())));
   web_loader_factory_->SetServiceWorkerURLLoaderFactory(
       std::move(service_worker_url_loader_factory));
 }
@@ -678,4 +689,13 @@ blink::WebString WebWorkerFetchContextImpl::GetAcceptLanguages() const {
   return blink::WebString::FromUTF8(renderer_preferences_.accept_languages);
 }
 
+void WebWorkerFetchContextImpl::AddPendingWorkerTimingReceiver(
+    int request_id,
+    mojo::PendingReceiver<blink::mojom::WorkerTimingContainer> receiver) {
+  // TODO(https://crbug.com/900700): Handle redirects properly. Currently on
+  // redirect, the receiver is replaced with a new one, discarding the timings
+  // before the redirect.
+  worker_timing_container_receivers_[request_id] = std::move(receiver);
+}
+
 }  // namespace content

content/renderer/loader/web_worker_fetch_context_impl.h

@@ -127,6 +127,8 @@ class CONTENT_EXPORT WebWorkerFetchContextImpl
   std::unique_ptr<blink::WebSocketHandshakeThrottle>
   CreateWebSocketHandshakeThrottle(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner) override;
+  mojo::ScopedMessagePipeHandle TakePendingWorkerTimingReceiver(
+      int request_id) override;
 
   // blink::mojom::ServiceWorkerWorkerClient implementation:
   void OnControllerChanged(blink::mojom::ControllerServiceWorkerMode) override;
@@ -172,8 +174,18 @@ class CONTENT_EXPORT WebWorkerFetchContextImpl
 
   blink::WebString GetAcceptLanguages() const override;
 
+  // Sets up |receiver| to receive resource performance timings for the given
+  // |request_id|. This receiver will be taken later by
+  // TakePendingWorkerTimingReceiver().
+  void AddPendingWorkerTimingReceiver(
+      int request_id,
+      mojo::PendingReceiver<blink::mojom::WorkerTimingContainer> receiver);
+
  private:
   class Factory;
+  using WorkerTimingContainerReceiverMap =
+      std::map<int /* request_id */,
+               mojo::PendingReceiver<blink::mojom::WorkerTimingContainer>>;
 
   // - |service_worker_client_receiver| receives OnControllerChanged()
   //   notifications.
@@ -346,6 +358,13 @@ class CONTENT_EXPORT WebWorkerFetchContextImpl
   std::unique_ptr<NavigationResponseOverrideParameters> response_override_;
 
   blink::AcceptLanguagesWatcher* accept_languages_watcher_ = nullptr;
+
+  // Contains pending receivers whose corresponding requests are still
+  // in-flight. The pending receivers are taken by
+  // TakePendingWorkerTimingReceiver() when the request is completed.
+  WorkerTimingContainerReceiverMap worker_timing_container_receivers_;
+
+  base::WeakPtrFactory<WebWorkerFetchContextImpl> weak_factory_{this};
 };
 
 }  // namespace content

content/renderer/service_worker/service_worker_fetch_context_impl.cc

@@ -191,4 +191,11 @@ blink::WebString ServiceWorkerFetchContextImpl::GetAcceptLanguages() const {
   return blink::WebString::FromUTF8(renderer_preferences_.accept_languages);
 }
 
+mojo::ScopedMessagePipeHandle
+ServiceWorkerFetchContextImpl::TakePendingWorkerTimingReceiver(int request_id) {
+  // No receiver exists because requests from service workers are never handled
+  // by a service worker.
+  return {};
+}
+
 }  // namespace content

content/renderer/service_worker/service_worker_fetch_context_impl.h

@@ -70,6 +70,8 @@ class CONTENT_EXPORT ServiceWorkerFetchContextImpl final
   CreateWebSocketHandshakeThrottle(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner) override;
   blink::WebString GetAcceptLanguages() const override;
+  mojo::ScopedMessagePipeHandle TakePendingWorkerTimingReceiver(
+      int request_id) override;
 
  private:
   ~ServiceWorkerFetchContextImpl() override;

third_party/blink/public/platform/web_worker_fetch_context.h

@@ -144,6 +144,12 @@ class WebWorkerFetchContext : public base::RefCounted<WebWorkerFetchContext> {
 
   // Returns the current list of user prefered languages.
   virtual blink::WebString GetAcceptLanguages() const = 0;
+
+  // Returns mojo::PendingReceiver<blink::mojom::blink::WorkerTimingContainer>
+  // for the blink::ResourceResponse with the given |request_id|. Null if the
+  // request has not been intercepted by a service worker.
+  virtual mojo::ScopedMessagePipeHandle TakePendingWorkerTimingReceiver(
+      int request_id) = 0;
 };
 
 }  // namespace blink

third_party/blink/renderer/core/loader/worker_fetch_context.cc

@@ -247,10 +247,12 @@ void WorkerFetchContext::PopulateResourceRequest(
 
 mojo::PendingReceiver<mojom::blink::WorkerTimingContainer>
 WorkerFetchContext::TakePendingWorkerTimingReceiver(int request_id) {
-  // TODO(https://crbug.com/900700): Take a pending receiver for
-  // WorkerTimingContainer from WebWorkerFetchContextImpl.
-  return mojo::NullReceiver();
+  mojo::ScopedMessagePipeHandle pipe =
+      GetWebWorkerFetchContext()->TakePendingWorkerTimingReceiver(request_id);
+  return mojo::PendingReceiver<mojom::blink::WorkerTimingContainer>(
+      std::move(pipe));
 }
+
 void WorkerFetchContext::SetFirstPartyCookie(ResourceRequest& out_request) {
   if (out_request.SiteForCookies().IsNull())
     out_request.SetSiteForCookies(GetSiteForCookies());

third_party/blink/renderer/modules/service_worker/web_embedded_worker_impl_test.cc

@@ -111,6 +111,10 @@ class FakeWebWorkerFetchContext final : public WebWorkerFetchContext {
     return base::Optional<WebSecurityOrigin>();
   }
   WebString GetAcceptLanguages() const override { return WebString(); }
+  mojo::ScopedMessagePipeHandle TakePendingWorkerTimingReceiver(
+      int request_id) override {
+    return {};
+  }
 
  private:
   FakeWebURLLoaderFactory fake_web_url_loader_factory_;