Test network annotation tags added to unittests in net/.

net/test/embedded_test_server/embedded_test_server_unittest.cc

Index: net/test/embedded_test_server/embedded_test_server_unittest.cc
diff --git a/net/test/embedded_test_server/embedded_test_server_unittest.cc b/net/test/embedded_test_server/embedded_test_server_unittest.cc
index 0794a78352c117af17f89754130687f0cee4e22c..fc647723170cca0fa57af9b851ed5b31f464ff86 100644
--- a/net/test/embedded_test_server/embedded_test_server_unittest.cc
+++ b/net/test/embedded_test_server/embedded_test_server_unittest.cc
@@ -458,8 +458,9 @@ TEST_P(EmbeddedTestServerTest, CloseDuringWrite) {
       &HandlePrefixedRequest, "/infinite", base::Bind(&HandleInfiniteRequest)));
   ASSERT_TRUE(server_->Start());
 
-  std::unique_ptr<URLRequest> request = context.CreateRequest(
-      server_->GetURL("/infinite"), DEFAULT_PRIORITY, &cancel_delegate);
+  std::unique_ptr<URLRequest> request =
+      context.CreateRequest(server_->GetURL("/infinite"), DEFAULT_PRIORITY,
+                            &cancel_delegate, TRAFFIC_ANNOTATION_FOR_TESTS);
   request->Start();
   cancel_delegate.WaitUntilDone();
 }