Fix webRequest not seeing events on redirect to service worker

When a request was redirected to a page with a service worker installed,
webRequest was not seeing the events. This is because the network loader
factory was no longer proxied on the redirect.

Bug: 1012977
Change-Id: I1161a8d6ac58711b83427accc8026a0981fa527e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2079932Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Commit-Queue: Clark DuVall <cduvall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745580}

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

@@ -2734,6 +2734,30 @@ IN_PROC_BROWSER_TEST_P(ServiceWorkerWebRequestApiTest,
   RunServiceWorkerFetchTest("empty.js");
 }
 
+IN_PROC_BROWSER_TEST_P(ServiceWorkerWebRequestApiTest,
+                       ServiceWorkerFallbackAfterRedirect) {
+  embedded_test_server()->ServeFilesFromSourceDirectory("content/test/data");
+  ASSERT_TRUE(embedded_test_server()->Start());
+
+  InstallRequestHeaderModifyingExtension();
+
+  RegisterServiceWorker("/fetch_event_passthrough.js", "/echoheader");
+
+  // Make sure the request is intercepted with no redirect.
+  ui_test_utils::NavigateToURL(
+      browser(), embedded_test_server()->GetURL("/echoheader?foo"));
+  content::WebContents* web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  EXPECT_EQ("bar", EvalJs(web_contents, "document.body.textContent;"));
+
+  // Make sure the request is intercepted with a redirect.
+  GURL redirect_url = embedded_test_server()->GetURL(
+      "/server-redirect?" +
+      embedded_test_server()->GetURL("/echoheader?foo").spec());
+  ui_test_utils::NavigateToURL(browser(), redirect_url);
+  EXPECT_EQ("bar", EvalJs(web_contents, "document.body.textContent;"));
+}
+
 // An extension should be able to modify the request header for service worker
 // script by using WebRequest API.
 IN_PROC_BROWSER_TEST_P(ServiceWorkerWebRequestApiTest, ServiceWorkerScript) {

content/browser/loader/navigation_url_loader_impl.cc

@@ -760,11 +760,14 @@ class NavigationURLLoaderImpl::URLLoaderRequestController
         DCHECK(proxied_factory_remote_.is_valid());
         // We don't worry about reconnection since it's a single navigation.
         network_loader_factory_->Clone(std::move(proxied_factory_receiver_));
-        factory = base::MakeRefCounted<network::WrapperSharedURLLoaderFactory>(
-            std::move(proxied_factory_remote_));
-      } else {
-        factory = network_loader_factory_;
+        // Replace the network factory with the proxied version since this may
+        // need to be used in redirects, and we've already consumed
+        // |proxied_factory_receiver_|.
+        network_loader_factory_ =
+            base::MakeRefCounted<network::WrapperSharedURLLoaderFactory>(
+                std::move(proxied_factory_remote_));
       }
+      factory = network_loader_factory_;
     }
     url_chain_.push_back(resource_request_->url);
     *out_options = GetURLLoaderOptions(