Add functionality to explicitly set SNI in the QUIC test client

net/tools/quic/test_tools/quic_test_client.cc

Index: net/tools/quic/test_tools/quic_test_client.cc
diff --git a/net/tools/quic/test_tools/quic_test_client.cc b/net/tools/quic/test_tools/quic_test_client.cc
index 760c451af1cfad29321941787cebb4052638fdaf..ebcf8c5175def65e98035e9964e48f8e70c182d1 100644
--- a/net/tools/quic/test_tools/quic_test_client.cc
+++ b/net/tools/quic/test_tools/quic_test_client.cc
@@ -303,9 +303,14 @@ ssize_t QuicTestClient::SendMessage(const HTTPMessage& message) {
   // If we're not connected, try to find an sni hostname.
   if (!connected()) {
     GURL url(message.headers()->request_uri().as_string());
-    if (!url.host().empty()) {
-      client_->set_server_id(QuicServerId(url.host(), url.EffectiveIntPort(),
-                                          PRIVACY_MODE_DISABLED));
+    if (override_sni_set_) {
+      client_->set_server_id(
+          QuicServerId(override_sni_, url.EffectiveIntPort(), PRIVACY_MODE_DISABLED));
+    } else {
+      if (!url.host().empty()) {
+        client_->set_server_id(
+            QuicServerId(url.host(), url.EffectiveIntPort(), PRIVACY_MODE_DISABLED));
+      }
     }
   }