LNA: Add use counters for WebRTC LNA

Add per page-load metrics for Local Network Access. This will help us
understand how often the LNA permission prompt will be shown.

Bug: 421223919
Change-Id: I6176447afd357ec286b53d228fe97328baa5b5a0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7042843
Reviewed-by: Guido Urdaneta <[email protected]>
Commit-Queue: Giovanni Ortuno Urquidi <[email protected]>
Reviewed-by: Harald Alvestrand <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1532382}

Author: Giovanni Ortuño Urquidi

third_party/blink/public/mojom/use_counter/metrics/web_feature.mojom

@@ -5016,6 +5016,10 @@ enum WebFeature {
   kTestReportBodyToJSON = 5701,
   kSpeculationRulesPrerenderUntilScript = 5702,
   kClipboardChangeEventChangeIdAttribute = 5703,
+  kWebRTCLocalNetworkAccessCheck = 5704,
+  kWebRTCLocalNetworkAccessPublicToLocal = 5705,
+  kWebRTCLocalNetworkAccessPublicToLoopback = 5706,
+  kWebRTCLocalNetworkAccessLocalToLoopback = 5707,
 
   // Add new features immediately above this line. Don't change assigned
   // numbers of any item, and don't reuse removed slots. Also don't add extra

third_party/blink/renderer/modules/peerconnection/peer_connection_dependency_factory.cc

@@ -85,6 +85,7 @@
 #include "third_party/blink/renderer/platform/peerconnection/vsync_provider.h"
 #include "third_party/blink/renderer/platform/peerconnection/vsync_tick_provider.h"
 #include "third_party/blink/renderer/platform/scheduler/public/post_cross_thread_task.h"
+#include "third_party/blink/renderer/platform/wtf/bind_post_task.h"
 #include "third_party/blink/renderer/platform/wtf/cross_thread_copier_base.h"
 #include "third_party/blink/renderer/platform/wtf/cross_thread_copier_gfx.h"
 #include "third_party/blink/renderer/platform/wtf/cross_thread_copier_mojo.h"
@@ -242,9 +243,12 @@ class LocalNetworkAccessPermission final
  public:
   explicit LocalNetworkAccessPermission(
       network::mojom::IPAddressSpace originator_address_space,
-      mojo::Remote<mojom::blink::PermissionService> permission_service)
+      mojo::Remote<mojom::blink::PermissionService> permission_service,
+      blink::CrossThreadRepeatingFunction<void(LocalNetworkAccessRequestType)>
+          count_callback)
       : originator_address_space_(originator_address_space),
-        permission_service_(std::move(permission_service)) {}
+        permission_service_(std::move(permission_service)),
+        count_callback_(std::move(count_callback)) {}
 
   ~LocalNetworkAccessPermission() override {
     DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
@@ -255,10 +259,11 @@ class LocalNetworkAccessPermission final
     DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
 
     const auto target_address_space = FromSocketAddress(candidate_address);
+    auto request_type = GetLocalNetworkAccessRequestType(
+        originator_address_space_, target_address_space);
     base::UmaHistogramEnumeration(
-        "WebRTC.PeerConnection.LocalNetworkAccess.RequestType",
-        GetLocalNetworkAccessRequestType(originator_address_space_,
-                                         target_address_space));
+        "WebRTC.PeerConnection.LocalNetworkAccess.RequestType", request_type);
+    count_callback_.Run(request_type);
 
     if (!RuntimeEnabledFeatures::LocalNetworkAccessWebRTCEnabled()) {
       return false;
@@ -312,6 +317,8 @@ class LocalNetworkAccessPermission final
       callback_;
   const network::mojom::IPAddressSpace originator_address_space_;
   mojo::Remote<mojom::blink::PermissionService> permission_service_;
+  blink::CrossThreadRepeatingFunction<void(LocalNetworkAccessRequestType)>
+      count_callback_;
 
   THREAD_CHECKER(thread_checker_);
 
@@ -342,7 +349,12 @@ class LocalNetworkAccessPermissionFactory final
             permission_service.BindNewPipeAndPassReceiver()));
 
     return std::make_unique<LocalNetworkAccessPermission>(
-        originator_address_space_, std::move(permission_service));
+        originator_address_space_, std::move(permission_service),
+        blink::BindPostTask(
+            main_thread_task_runner_,
+            CrossThreadBindRepeating(
+                &PeerConnectionDependencyFactory::CountLocalNetworkAccess,
+                MakeUnwrappingCrossThreadWeakHandle(factory_))));
   }
 
  private:
@@ -1323,4 +1335,38 @@ PeerConnectionDependencyFactory::
   return std::make_unique<LocalNetworkAccessPermissionFactory>(this);
 }
 
+void PeerConnectionDependencyFactory::CountLocalNetworkAccess(
+    LocalNetworkAccessRequestType request_type) {
+  UseCounter::Count(DomWindow(),
+                    mojom::blink::WebFeature::kWebRTCLocalNetworkAccessCheck);
+
+  switch (request_type) {
+    // To same or more public cases:
+    case LocalNetworkAccessRequestType::kUnknown:
+    case LocalNetworkAccessRequestType::kPublicToPublic:
+    case LocalNetworkAccessRequestType::kLocalToPublic:
+    case LocalNetworkAccessRequestType::kLocalToLocal:
+    case LocalNetworkAccessRequestType::kLoopbackToPublic:
+    case LocalNetworkAccessRequestType::kLoopbackToLocal:
+    case LocalNetworkAccessRequestType::kLoopbackToLoopback:
+      return;
+    // To less public cases:
+    case LocalNetworkAccessRequestType::kPublicToLocal:
+      UseCounter::Count(
+          DomWindow(),
+          mojom::blink::WebFeature::kWebRTCLocalNetworkAccessPublicToLocal);
+      return;
+    case LocalNetworkAccessRequestType::kPublicToLoopback:
+      UseCounter::Count(
+          DomWindow(),
+          mojom::blink::WebFeature::kWebRTCLocalNetworkAccessPublicToLoopback);
+      return;
+    case LocalNetworkAccessRequestType::kLocalToLoopback:
+      UseCounter::Count(
+          DomWindow(),
+          mojom::blink::WebFeature::kWebRTCLocalNetworkAccessLocalToLoopback);
+      return;
+  }
+}
+
 }  // namespace blink

third_party/blink/renderer/modules/peerconnection/peer_connection_dependency_factory.h

@@ -173,6 +173,7 @@ class MODULES_EXPORT PeerConnectionDependencyFactory
   void BindPermissionService(
       mojo::PendingReceiver<mojom::blink::PermissionService>
           permission_service);
+  void CountLocalNetworkAccess(LocalNetworkAccessRequestType);
 
   std::unique_ptr<webrtc::LocalNetworkAccessPermissionFactoryInterface>
   CreateLocalNetworkAccessPermissionFactoryForTesting();

third_party/blink/renderer/modules/peerconnection/peer_connection_dependency_factory_test.cc

@@ -9,6 +9,7 @@
 #include "base/notreached.h"
 #include "base/strings/strcat.h"
 #include "base/strings/to_string.h"
+#include "base/task/current_thread.h"
 #include "base/test/metrics/histogram_tester.h"
 #include "base/test/scoped_feature_list.h"
 #include "mojo/public/cpp/bindings/pending_associated_remote.h"
@@ -18,7 +19,9 @@
 #include "third_party/blink/public/platform/scheduler/test/renderer_scheduler_test_support.h"
 #include "third_party/blink/public/platform/web_runtime_features.h"
 #include "third_party/blink/renderer/bindings/core/v8/v8_binding_for_testing.h"
+#include "third_party/blink/renderer/core/dom/document.h"
 #include "third_party/blink/renderer/core/frame/policy_container.h"
+#include "third_party/blink/renderer/core/frame/web_feature.h"
 #include "third_party/blink/renderer/modules/peerconnection/mock_peer_connection_dependency_factory.h"
 #include "third_party/blink/renderer/modules/peerconnection/mock_rtc_peer_connection_handler_client.h"
 #include "third_party/blink/renderer/modules/peerconnection/rtc_peer_connection_handler.h"
@@ -114,6 +117,27 @@ class LocalNetworkAccessPeerConnectionDependencyFactoryTest
   }
 
  protected:
+  void TestUseCounters(Document& document,
+                       LocalNetworkAccessRequestType request_type) {
+    base::test::RunUntil([&]() {
+      return document.IsUseCounted(
+          mojom::blink::WebFeature::kWebRTCLocalNetworkAccessCheck);
+    });
+
+    EXPECT_EQ(
+        request_type == LocalNetworkAccessRequestType::kPublicToLocal,
+        document.IsUseCounted(
+            mojom::blink::WebFeature::kWebRTCLocalNetworkAccessPublicToLocal));
+    EXPECT_EQ(
+        request_type == LocalNetworkAccessRequestType::kPublicToLoopback,
+        document.IsUseCounted(mojom::blink::WebFeature::
+                                  kWebRTCLocalNetworkAccessPublicToLoopback));
+    EXPECT_EQ(
+        request_type == LocalNetworkAccessRequestType::kLocalToLoopback,
+        document.IsUseCounted(mojom::blink::WebFeature::
+                                  kWebRTCLocalNetworkAccessLocalToLoopback));
+  }
+
   base::test::ScopedFeatureList feature_list_;
   base::HistogramTester histogram_tester_;
 };
@@ -225,6 +249,7 @@ TEST_P(LocalNetworkAccessPeerConnectionDependencyFactoryTest,
 
   histogram_tester_.ExpectUniqueSample(
       "WebRTC.PeerConnection.LocalNetworkAccess.RequestType", request_type, 1);
+  TestUseCounters(scope.GetDocument(), request_type);
 }
 
 TEST_P(LocalNetworkAccessPeerConnectionDependencyFactoryTest,
@@ -255,6 +280,7 @@ TEST_P(LocalNetworkAccessPeerConnectionDependencyFactoryTest,
 
   histogram_tester_.ExpectUniqueSample(
       "WebRTC.PeerConnection.LocalNetworkAccess.RequestType", request_type, 1);
+  TestUseCounters(scope.GetDocument(), request_type);
 }
 
 }  // namespace blink

tools/metrics/histograms/metadata/blink/enums.xml

@@ -6333,6 +6333,10 @@ Called by update_use_counter_feature_enum.py.-->
   <int value="5701" label="TestReportBodyToJSON"/>
   <int value="5702" label="SpeculationRulesPrerenderUntilScript"/>
   <int value="5703" label="ClipboardChangeEventChangeIdAttribute"/>
+  <int value="5704" label="WebRTCLocalNetworkAccessCheck"/>
+  <int value="5705" label="WebRTCLocalNetworkAccessPublicToLocal"/>
+  <int value="5706" label="WebRTCLocalNetworkAccessPublicToLoopback"/>
+  <int value="5707" label="WebRTCLocalNetworkAccessLocalToLoopback"/>
 </enum>
 
 <!-- LINT.ThenChange(//third_party/blink/public/mojom/use_counter/metrics/web_feature.mojom:WebFeature) -->