Deprecate FLAGS_quic_buffer_packet_till_chlo.

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 f1cf61d8fa396a1a1ee618754f4a376312834cb7..5fa993152138e73dc3f4b5a67b34d5abd5a90de5 100644
--- a/net/tools/quic/end_to_end_test.cc
+++ b/net/tools/quic/end_to_end_test.cc
@@ -86,8 +86,7 @@ struct TestParams {
              QuicTag congestion_control_tag,
              bool disable_hpack_dynamic_table,
              bool force_hol_blocking,
-             bool use_cheap_stateless_reject,
-             bool buffer_packet_till_chlo)
+             bool use_cheap_stateless_reject)
       : client_supported_versions(client_supported_versions),
         server_supported_versions(server_supported_versions),
         negotiated_version(negotiated_version),
@@ -97,8 +96,7 @@ struct TestParams {
         congestion_control_tag(congestion_control_tag),
         disable_hpack_dynamic_table(disable_hpack_dynamic_table),
         force_hol_blocking(force_hol_blocking),
-        use_cheap_stateless_reject(use_cheap_stateless_reject),
-        buffer_packet_till_chlo(buffer_packet_till_chlo) {}
+        use_cheap_stateless_reject(use_cheap_stateless_reject) {}
 
   friend ostream& operator<<(ostream& os, const TestParams& p) {
     os << "{ server_supported_versions: "
@@ -114,8 +112,8 @@ struct TestParams {
        << QuicUtils::TagToString(p.congestion_control_tag);
     os << " disable_hpack_dynamic_table: " << p.disable_hpack_dynamic_table;
     os << " force_hol_blocking: " << p.force_hol_blocking;
-    os << " use_cheap_stateless_reject: " << p.use_cheap_stateless_reject;
-    os << " buffer_packet_till_chlo: " << p.buffer_packet_till_chlo << " }";
+    os << " use_cheap_stateless_reject: " << p.use_cheap_stateless_reject
+       << " }";
     return os;
   }
 
@@ -128,7 +126,6 @@ struct TestParams {
   bool disable_hpack_dynamic_table;
   bool force_hol_blocking;
   bool use_cheap_stateless_reject;
-  bool buffer_packet_till_chlo;
 };
 
 // Constructs various test permutations.
@@ -163,7 +160,7 @@ std::vector<TestParams> GetTestParams() {
 
   // This must be kept in sync with the number of nested for-loops below as it
   // is used to prune the number of tests that are run.
-  const int kMaxEnabledOptions = 6;
+  const int kMaxEnabledOptions = 5;
   int max_enabled_options = 0;
   std::vector<TestParams> params;
   for (bool server_uses_stateless_rejects_if_peer_supported : {true, false}) {
@@ -172,94 +169,79 @@ std::vector<TestParams> GetTestParams() {
         for (bool disable_hpack_dynamic_table : {false}) {
           for (bool force_hol_blocking : {true, false}) {
             for (bool use_cheap_stateless_reject : {true, false}) {
-              for (bool buffer_packet_till_chlo : {true, false}) {
-                if (!buffer_packet_till_chlo && use_cheap_stateless_reject) {
-                  // Doing stateless reject while not buffering packet
-                  // before CHLO is not allowed.
-                  break;
-                }
-                int enabled_options = 0;
-                if (force_hol_blocking) {
-                  ++enabled_options;
-                }
-                if (congestion_control_tag != kQBIC) {
-                  ++enabled_options;
-                }
-                if (disable_hpack_dynamic_table) {
-                  ++enabled_options;
-                }
-                if (client_supports_stateless_rejects) {
-                  ++enabled_options;
-                }
-                if (server_uses_stateless_rejects_if_peer_supported) {
-                  ++enabled_options;
-                }
-                if (buffer_packet_till_chlo) {
-                  ++enabled_options;
-                }
-                if (use_cheap_stateless_reject) {
-                  ++enabled_options;
-                }
-                CHECK_GE(kMaxEnabledOptions, enabled_options);
-                if (enabled_options > max_enabled_options) {
-                  max_enabled_options = enabled_options;
+              int enabled_options = 0;
+              if (force_hol_blocking) {
+                ++enabled_options;
+              }
+              if (congestion_control_tag != kQBIC) {
+                ++enabled_options;
+              }
+              if (disable_hpack_dynamic_table) {
+                ++enabled_options;
+              }
+              if (client_supports_stateless_rejects) {
+                ++enabled_options;
+              }
+              if (server_uses_stateless_rejects_if_peer_supported) {
+                ++enabled_options;
+              }
+              if (use_cheap_stateless_reject) {
+                ++enabled_options;
+              }
+              CHECK_GE(kMaxEnabledOptions, enabled_options);
+              if (enabled_options > max_enabled_options) {
+                max_enabled_options = enabled_options;
+              }
+
+              // Run tests with no options, a single option, or all the
+              // options enabled to avoid a combinatorial explosion.
+              if (enabled_options > 1 && enabled_options < kMaxEnabledOptions) {
+                continue;
+              }
+
+              for (const QuicVersionVector& client_versions : version_buckets) {
+                CHECK(!client_versions.empty());
+                if (FilterSupportedVersions(client_versions).empty()) {
+                  continue;
                 }
-
-                // Run tests with no options, a single option, or all the
-                // options enabled to avoid a combinatorial explosion.
+                // Add an entry for server and client supporting all
+                // versions.
+                params.push_back(TestParams(
+                    client_versions, all_supported_versions,
+                    client_versions.front(), client_supports_stateless_rejects,
+                    server_uses_stateless_rejects_if_peer_supported,
+                    congestion_control_tag, disable_hpack_dynamic_table,
+                    force_hol_blocking, use_cheap_stateless_reject));
+
+                // Run version negotiation tests tests with no options, or
+                // all the options enabled to avoid a combinatorial
+                // explosion.
                 if (enabled_options > 1 &&
                     enabled_options < kMaxEnabledOptions) {
                   continue;
                 }
 
-                for (const QuicVersionVector& client_versions :
-                     version_buckets) {
-                  CHECK(!client_versions.empty());
-                  if (FilterSupportedVersions(client_versions).empty()) {
+                // Test client supporting all versions and server supporting
+                // 1 version. Simulate an old server and exercise version
+                // downgrade in the client. Protocol negotiation should
+                // occur.  Skip the i = 0 case because it is essentially the
+                // same as the default case.
+                for (size_t i = 1; i < client_versions.size(); ++i) {
+                  QuicVersionVector server_supported_versions;
+                  server_supported_versions.push_back(client_versions[i]);
+                  if (FilterSupportedVersions(server_supported_versions)
+                          .empty()) {
                     continue;
                   }
-                  // Add an entry for server and client supporting all
-                  // versions.
                   params.push_back(TestParams(
-                      client_versions, all_supported_versions,
-                      client_versions.front(),
+                      client_versions, server_supported_versions,
+                      server_supported_versions.front(),
                       client_supports_stateless_rejects,
                       server_uses_stateless_rejects_if_peer_supported,
                       congestion_control_tag, disable_hpack_dynamic_table,
-                      force_hol_blocking, use_cheap_stateless_reject,
-                      buffer_packet_till_chlo));
-
-                  // Run version negotiation tests tests with no options, or
-                  // all the options enabled to avoid a combinatorial
-                  // explosion.
-                  if (enabled_options > 1 &&
-                      enabled_options < kMaxEnabledOptions) {
-                    continue;
-                  }
-
-                  // Test client supporting all versions and server supporting
-                  // 1 version. Simulate an old server and exercise version
-                  // downgrade in the client. Protocol negotiation should
-                  // occur.  Skip the i = 0 case because it is essentially the
-                  // same as the default case.
-                  for (size_t i = 1; i < client_versions.size(); ++i) {
-                    QuicVersionVector server_supported_versions;
-                    server_supported_versions.push_back(client_versions[i]);
-                    if (FilterSupportedVersions(server_supported_versions)
-                            .empty()) {
-                      continue;
-                    }
-                    params.push_back(TestParams(
-                        client_versions, server_supported_versions,
-                        server_supported_versions.front(),
-                        client_supports_stateless_rejects,
-                        server_uses_stateless_rejects_if_peer_supported,
-                        congestion_control_tag, disable_hpack_dynamic_table,
-                        force_hol_blocking, use_cheap_stateless_reject,
-                        buffer_packet_till_chlo));
+                      force_hol_blocking, use_cheap_stateless_reject));
                   }    // End of version for loop.
                 }      // End of 2nd version for loop.
-              }        // End of buffer_packet_till_chlo loop.
             }          // End of use_cheap_stateless_reject for loop.
           }            // End of force_hol_blocking loop.
         }              // End of disable_hpack_dynamic_table for loop.
@@ -453,12 +435,9 @@ class EndToEndTest : public ::testing::TestWithParam<TestParams> {
   }
 
   void StartServer() {
-    FLAGS_quic_buffer_packet_till_chlo = GetParam().buffer_packet_till_chlo;
     FLAGS_quic_use_cheap_stateless_rejects =
         GetParam().use_cheap_stateless_reject;
-    if (!FLAGS_quic_buffer_packet_till_chlo) {
-      FLAGS_quic_limit_num_new_sessions_per_epoll_loop = false;
-    }
+
     auto test_server =
         new QuicTestServer(CryptoTestUtils::ProofSourceForTesting(),
                            server_config_, server_supported_versions_);
@@ -2965,10 +2944,6 @@ TEST_P(EndToEndTest, ReleaseHeadersStreamBufferWhenIdle) {
 
 class EndToEndBufferedPacketsTest : public EndToEndTest {
  public:
-  EndToEndBufferedPacketsTest() : EndToEndTest() {
-    FLAGS_quic_buffer_packet_till_chlo = true;
-  }
-
   void CreateClientWithWriter() override {
     LOG(ERROR) << "create client with reorder_writer_ ";
     reorder_writer_ = new PacketReorderingWriter();