Count use of Service Worker network fallback with used request body

In order to fix crbug.com/1167013, we need to introduce a breaking
change. Introduce a use counter to estimate the size of the impact.

Bug: 1167014
Change-Id: I6f525aa8ec38fa1fa964f4ede3d1f55863d705d2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2631550
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Auto-Submit: Yutaka Hirano <yhirano@chromium.org>
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#844027}

third_party/blink/public/mojom/web_feature/web_feature.mojom

@@ -3092,6 +3092,7 @@ enum WebFeature {
   kAddressSpaceUnknownSecureContextNavigatedToPrivate = 3771,
   kAddressSpaceUnknownNonSecureContextNavigatedToPrivate = 3772,
   kRTCPeerConnectionSdpSemanticsPlanB = 3773,
+  kFetchRespondWithNoResponseWithUsedRequestBody = 3774,
 
   // Add new features immediately above this line. Don't change assigned
   // numbers of any item, and don't reuse removed slots.

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

@@ -24,6 +24,7 @@
 #include "third_party/blink/renderer/core/execution_context/execution_context.h"
 #include "third_party/blink/renderer/core/fetch/body_stream_buffer.h"
 #include "third_party/blink/renderer/core/inspector/console_message.h"
+#include "third_party/blink/renderer/core/streams/readable_stream.h"
 #include "third_party/blink/renderer/modules/service_worker/cross_origin_resource_policy_checker.h"
 #include "third_party/blink/renderer/modules/service_worker/fetch_event.h"
 #include "third_party/blink/renderer/modules/service_worker/service_worker_global_scope.h"
@@ -375,6 +376,11 @@ void FetchRespondWithObserver::OnResponseFulfilled(
 
 void FetchRespondWithObserver::OnNoResponse() {
   DCHECK(GetExecutionContext());
+  if (request_body_stream_ && (request_body_stream_->IsLocked() ||
+                               request_body_stream_->IsDisturbed())) {
+    GetExecutionContext()->CountUse(
+        WebFeature::kFetchRespondWithNoResponseWithUsedRequestBody);
+  }
   ServiceWorkerGlobalScope* service_worker_global_scope =
       To<ServiceWorkerGlobalScope>(GetExecutionContext());
   service_worker_global_scope->RespondToFetchEventWithNoResponse(
@@ -382,6 +388,17 @@ void FetchRespondWithObserver::OnNoResponse() {
   event_->ResolveHandledPromise();
 }
 
+void FetchRespondWithObserver::SetEvent(FetchEvent* event) {
+  DCHECK(!event_);
+  DCHECK(!request_body_stream_);
+  event_ = event;
+  // We don't use Body::body() in order to avoid accidental CountUse calls.
+  BodyStreamBuffer* body_buffer = event_->request()->BodyBuffer();
+  if (body_buffer) {
+    request_body_stream_ = body_buffer->Stream();
+  }
+}
+
 FetchRespondWithObserver::FetchRespondWithObserver(
     ExecutionContext* context,
     int fetch_event_id,
@@ -399,6 +416,7 @@ FetchRespondWithObserver::FetchRespondWithObserver(
 
 void FetchRespondWithObserver::Trace(Visitor* visitor) const {
   visitor->Trace(event_);
+  visitor->Trace(request_body_stream_);
   RespondWithObserver::Trace(visitor);
 }
 

third_party/blink/renderer/modules/service_worker/fetch_respond_with_observer.h

@@ -18,6 +18,7 @@ namespace blink {
 class CrossOriginResourcePolicyChecker;
 class ExecutionContext;
 class FetchEvent;
+class ReadableStream;
 class ScriptValue;
 class WaitUntilObserver;
 
@@ -47,10 +48,7 @@ class MODULES_EXPORT FetchRespondWithObserver : public RespondWithObserver {
                            const char* property_name) override;
   void OnNoResponse() override;
 
-  void SetEvent(FetchEvent* event) {
-    DCHECK(!event_);
-    event_ = event;
-  }
+  void SetEvent(FetchEvent* event);
 
   void Trace(Visitor*) const override;
 
@@ -61,6 +59,7 @@ class MODULES_EXPORT FetchRespondWithObserver : public RespondWithObserver {
   const mojom::RequestContextFrameType frame_type_;
   const network::mojom::RequestDestination request_destination_;
   Member<FetchEvent> event_;
+  Member<ReadableStream> request_body_stream_;
   base::WeakPtr<CrossOriginResourcePolicyChecker> corp_checker_;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 };

tools/metrics/histograms/enums.xml

@@ -30998,6 +30998,7 @@ Called by update_use_counter_feature_enum.py.-->
   <int value="3772"
       label="AddressSpaceUnknownNonSecureContextNavigatedToPrivate"/>
   <int value="3773" label="RTCPeerConnectionSdpSemanticsPlanB"/>
+  <int value="3774" label="FetchRespondWithNoResponseWithUsedRequestBody"/>
 </enum>
 
 <enum name="FeaturePolicyAllowlistType">