[Extensions] Remove webRequest data when a BrowserContext is destroyed.

The ExtensionWebRequestRouter is a singleton object that can outlive
a BrowserContext. This CL clears any data related to a BrowserContext
when it's destroyed.

Bug: 1024211
Change-Id: Idd77a089c284037c08e8737b36402fcaf4bd4646
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3445250
Reviewed-by: Devlin Cronin <rdevlin.cronin@chromium.org>
Commit-Queue: David Bertoni <dbertoni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#969698}

chrome/browser/extensions/api/web_request/web_request_api_unittest.cc

@@ -190,6 +190,83 @@ TEST_F(ExtensionWebRequestTest, AddAndRemoveListeners) {
           &profile_, kEventName));
 }
 
+// Tests that when a browser_context shuts down, all data keyed to that
+// context is removed.
+TEST_F(ExtensionWebRequestTest, BrowserContextShutdown) {
+  ExtensionWebRequestEventRouter* const event_router =
+      ExtensionWebRequestEventRouter::GetInstance();
+  ASSERT_TRUE(event_router);
+
+  std::string ext_id("abcdefghijklmnopabcdefghijklmnop");
+  ExtensionWebRequestEventRouter::RequestFilter filter;
+  const std::string kEventName(web_request::OnBeforeRequest::kEventName);
+  const std::string kSubEventName = kEventName + "/1";
+  EXPECT_EQ(0u,
+            event_router->GetListenerCountForTesting(&profile_, kEventName));
+  EXPECT_FALSE(event_router->HasAnyExtraHeadersListenerImpl(&profile_));
+
+  // Add two listeners for the main profile.
+  event_router->AddEventListener(
+      &profile_, ext_id, ext_id, events::FOR_TEST, kEventName, kSubEventName,
+      filter, 0, 1 /* render_process_id */, 0, extensions::kMainThreadId,
+      blink::mojom::kInvalidServiceWorkerVersionId);
+  event_router->AddEventListener(
+      &profile_, ext_id, ext_id, events::FOR_TEST, kEventName, kSubEventName,
+      filter, 0, 2 /* render_process_id */, 0, extensions::kMainThreadId,
+      blink::mojom::kInvalidServiceWorkerVersionId);
+  event_router->IncrementExtraHeadersListenerCount(&profile_);
+  EXPECT_EQ(2u,
+            event_router->GetListenerCountForTesting(&profile_, kEventName));
+  EXPECT_TRUE(event_router->HasAnyExtraHeadersListenerImpl(&profile_));
+
+  // Create an off-the-record profile.
+  auto otr_profile_id = Profile::OTRProfileID::CreateUniqueForTesting();
+  Profile* const otr_profile =
+      profile_.GetOffTheRecordProfile(otr_profile_id,
+                                      /*create_if_needed=*/true);
+  ASSERT_TRUE(otr_profile);
+
+  // Because the ExtensionWebRequestEventRouter is a singleton, there are hooks
+  // in the off-the-record profile for notifying it when an OTR profile is
+  // created and destroyed. Unfortunately, that doesn't work with test profiles,
+  // so the test needs to simulate those calls
+  event_router->OnOTRBrowserContextCreated(&profile_, otr_profile);
+  EXPECT_EQ(2u, event_router->cross_browser_context_map_.size());
+  EXPECT_EQ(0u,
+            event_router->GetListenerCountForTesting(otr_profile, kEventName));
+  EXPECT_FALSE(event_router->HasAnyExtraHeadersListenerImpl(otr_profile));
+
+  // Add two listeners for the otr profile.
+  event_router->AddEventListener(
+      otr_profile, ext_id, ext_id, events::FOR_TEST, kEventName, kSubEventName,
+      filter, 0, 1 /* render_process_id */, 0, extensions::kMainThreadId,
+      blink::mojom::kInvalidServiceWorkerVersionId);
+  event_router->AddEventListener(
+      otr_profile, ext_id, ext_id, events::FOR_TEST, kEventName, kSubEventName,
+      filter, 0, 2 /* render_process_id */, 0, extensions::kMainThreadId,
+      blink::mojom::kInvalidServiceWorkerVersionId);
+  event_router->IncrementExtraHeadersListenerCount(otr_profile);
+  EXPECT_EQ(2u,
+            event_router->GetListenerCountForTesting(otr_profile, kEventName));
+  EXPECT_TRUE(event_router->HasAnyExtraHeadersListenerImpl(otr_profile));
+
+  // Simulate the OTR being destroyed.
+  event_router->OnOTRBrowserContextDestroyed(&profile_, otr_profile);
+  EXPECT_EQ(0u, event_router->cross_browser_context_map_.size());
+  EXPECT_EQ(0u,
+            event_router->GetListenerCountForTesting(otr_profile, kEventName));
+  EXPECT_FALSE(event_router->HasAnyExtraHeadersListenerImpl(otr_profile));
+
+  // We can't just delete the profile, because the call comes through the
+  // WebRequestAPI instance for that profile, and creating that requires
+  // more infrastucture than it's worth. Instead, simulate it with a call
+  // into the event router directly.
+  event_router->OnBrowserContextShutdown(&profile_);
+  EXPECT_EQ(0u,
+            event_router->GetListenerCountForTesting(&profile_, kEventName));
+  EXPECT_FALSE(event_router->HasAnyExtraHeadersListenerImpl(&profile_));
+}
+
 namespace {
 
 void TestInitFromValue(content::BrowserContext* browser_context,

extensions/browser/api/web_request/web_request_api.cc

@@ -649,6 +649,8 @@ void WebRequestAPI::Shutdown() {
   proxies_.reset();
   EventRouter::Get(browser_context_)->UnregisterObserver(this);
   extensions::ExtensionRegistry::Get(browser_context_)->RemoveObserver(this);
+  ExtensionWebRequestEventRouter::GetInstance()->OnBrowserContextShutdown(
+      browser_context_);
 }
 
 static base::LazyInstance<
@@ -1818,6 +1820,7 @@ void ExtensionWebRequestEventRouter::OnOTRBrowserContextDestroyed(
     content::BrowserContext* otr_browser_context) {
   cross_browser_context_map_.erase(otr_browser_context);
   cross_browser_context_map_.erase(original_browser_context);
+  OnBrowserContextShutdown(otr_browser_context);
 }
 
 void ExtensionWebRequestEventRouter::AddCallbackForPageLoad(
@@ -1875,7 +1878,6 @@ void ExtensionWebRequestEventRouter::IncrementExtraHeadersListenerCount(
     // We only keep values greater than 0 in the map.
     DCHECK_GT(result.first->second, 0);
     result.first->second++;
-    return;
   }
 }
 
@@ -1891,6 +1893,12 @@ void ExtensionWebRequestEventRouter::DecrementExtraHeadersListenerCount(
   extra_headers_listener_count_.erase(it);
 }
 
+void ExtensionWebRequestEventRouter::OnBrowserContextShutdown(
+    content::BrowserContext* browser_context) {
+  listeners_.erase(browser_context);
+  extra_headers_listener_count_.erase(browser_context);
+}
+
 bool ExtensionWebRequestEventRouter::HasAnyExtraHeadersListenerImpl(
     content::BrowserContext* browser_context) {
   return base::Contains(extra_headers_listener_count_, browser_context);

extensions/browser/api/web_request/web_request_api.h

@@ -534,25 +534,14 @@ class ExtensionWebRequestEventRouter {
   void DecrementExtraHeadersListenerCount(
       content::BrowserContext* browser_context);
 
+  // Called when a BrowserContext is being destroyed.
+  void OnBrowserContextShutdown(content::BrowserContext* browser_context);
+
  private:
   friend class WebRequestAPI;
   friend class base::NoDestructor<ExtensionWebRequestEventRouter>;
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest,
-                           BlockingEventPrecedenceRedirect);
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest,
-                           BlockingEventPrecedenceCancel);
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest,
-                           SimulateChancelWhileBlocked);
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest, AccessRequestBodyData);
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest,
-                           MinimalAccessRequestBodyData);
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest,
-                           ProperFilteringInPublicSession);
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest, NoAccessRequestBodyData);
   FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest, AddAndRemoveListeners);
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest, BlockedRequestsAreRemoved);
-  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestHeaderModificationTest,
-                           TestModifications);
+  FRIEND_TEST_ALL_PREFIXES(ExtensionWebRequestTest, BrowserContextShutdown);
 
   struct EventListener {
     // TODO(rdevlin.cronin): There are two types of EventListeners - those