Remove support for QUIC_VERSION_16.

net/tools/quic/end_to_end_test.cc

Index: net/tools/quic/end_to_end_test.cc
diff --git a/net/tools/quic/end_to_end_test.cc b/net/tools/quic/end_to_end_test.cc
index 200926d810d4850168b141f4506f31f535fba642..23ba536726417a567cee530ccf5f7c25ac476731 100644
--- a/net/tools/quic/end_to_end_test.cc
+++ b/net/tools/quic/end_to_end_test.cc
@@ -139,12 +139,6 @@ vector<TestParams> GetTestParams() {
         for (size_t i = 1; i < all_supported_versions.size(); ++i) {
           QuicVersionVector server_supported_versions;
           server_supported_versions.push_back(all_supported_versions[i]);
-          if (all_supported_versions[i] >= QUIC_VERSION_18) {
-            // Until flow control is globally rolled out and we remove
-            // QUIC_VERSION_16, the server MUST support at least one QUIC
-            // version that does not use flow control.
-            server_supported_versions.push_back(QUIC_VERSION_16);
-          }
           params.push_back(TestParams(all_supported_versions,
                                       server_supported_versions,
                                       server_supported_versions[0],
@@ -693,14 +687,6 @@ TEST_P(EndToEndTest, LargePostZeroRTTFailure) {
 
   // The 0-RTT handshake should succeed.
   client_->Connect();
-  if (client_supported_versions_[0] >= QUIC_VERSION_18 &&
-      negotiated_version_ <= QUIC_VERSION_16) {
-    // If the version negotiation has resulted in a downgrade, then the client
-    // must wait for the handshake to complete before sending any data.
-    // Otherwise it may have queued frames which will trigger a
-    // DFATAL when they are serialized after the downgrade.
-    client_->client()->WaitForCryptoHandshakeConfirmed();
-  }
   client_->WaitForResponseForMs(-1);
   ASSERT_TRUE(client_->client()->connected());
   EXPECT_EQ(kFooResponseBody, client_->SendCustomSynchronousRequest(request));
@@ -714,14 +700,6 @@ TEST_P(EndToEndTest, LargePostZeroRTTFailure) {
   StartServer();
 
   client_->Connect();
-  if (client_supported_versions_[0] >= QUIC_VERSION_18 &&
-      negotiated_version_ <= QUIC_VERSION_16) {
-    // If the version negotiation has resulted in a downgrade, then the client
-    // must wait for the handshake to complete before sending any data.
-    // Otherwise it may have queued frames which will trigger a
-    // DFATAL when they are serialized after the downgrade.
-    client_->client()->WaitForCryptoHandshakeConfirmed();
-  }
   ASSERT_TRUE(client_->client()->connected());
   EXPECT_EQ(kFooResponseBody, client_->SendCustomSynchronousRequest(request));
   EXPECT_EQ(2, client_->client()->session()->GetNumSentClientHellos());