Re-enable reading list tests

ios/web/public/test/http_server/http_server.mm

Index: ios/web/public/test/http_server/http_server.mm
diff --git a/ios/web/public/test/http_server/http_server.mm b/ios/web/public/test/http_server/http_server.mm
index 6c6219fe543821b15136249537b69d097f3e0844..8e30abcaf458f0cd6119dbb202a3d32bfc5e7ea0 100644
--- a/ios/web/public/test/http_server/http_server.mm
+++ b/ios/web/public/test/http_server/http_server.mm
@@ -70,6 +70,9 @@ HttpServer& HttpServer::GetSharedInstanceWithResponseProviders(
 
 std::unique_ptr<net::test_server::HttpResponse> HttpServer::GetResponse(
     const net::test_server::HttpRequest& request) {
+  if (isSuspended) {
+    return base::MakeUnique<net::test_server::HungResponse>();
+  }
   ResponseProvider::Request provider_request =
       ResponseProviderRequestFromEmbeddedTestServerRequest(request);
   ResponseProvider* response_provider =
@@ -109,6 +112,7 @@ void HttpServer::StartOrDie() {
   if (embedded_test_server_->Start()) {
     SetPort((NSUInteger)embedded_test_server_->port());
   }
+  isSuspended = NO;
   CHECK(IsRunning());
 }
 
@@ -122,6 +126,10 @@ void HttpServer::Stop() {
   SetPort(0);
 }
 
+void HttpServer::SetSuspend(bool suspended) {
+  isSuspended = suspended;
+}
+
 bool HttpServer::IsRunning() const {
   DCHECK([NSThread isMainThread]);
   if (embedded_test_server_ == nullptr) {