Update from https://crrev.com/306655

net/quic/quic_session.cc

Index: net/quic/quic_session.cc
diff --git a/net/quic/quic_session.cc b/net/quic/quic_session.cc
index e4b163f30f3ff1d90f2793c21ac43ce8a647f0cc..f05395e77f56bf3c617e4ed8604de6bb3fbe3722 100644
--- a/net/quic/quic_session.cc
+++ b/net/quic/quic_session.cc
@@ -7,7 +7,6 @@
 #include "base/stl_util.h"
 #include "net/quic/crypto/proof_verifier.h"
 #include "net/quic/quic_connection.h"
-#include "net/quic/quic_flags.h"
 #include "net/quic/quic_flow_controller.h"
 #include "net/quic/quic_headers_stream.h"
 #include "net/ssl/ssl_info.h"
@@ -438,7 +437,7 @@ void QuicSession::UpdateFlowControlOnFinalReceivedByteOffset(
 
   DVLOG(1) << ENDPOINT << "Received final byte offset " << final_byte_offset
            << " for stream " << stream_id;
-  uint64 offset_diff = final_byte_offset - it->second;
+  QuicByteCount offset_diff = final_byte_offset - it->second;
   if (flow_controller_->UpdateHighestReceivedOffset(
       flow_controller_->highest_received_byte_offset() + offset_diff)) {
     // If the final offset violates flow control, close the connection now.
@@ -465,20 +464,18 @@ void QuicSession::OnConfigNegotiated() {
   connection_->SetFromConfig(config_);
   QuicVersion version = connection()->version();
 
-  if (FLAGS_quic_allow_more_open_streams) {
-    uint32 max_streams = config_.MaxStreamsPerConnection();
-    if (is_server()) {
-      // A server should accept a small number of additional streams beyond the
-      // limit sent to the client. This helps avoid early connection termination
-      // when FIN/RSTs for old streams are lost or arrive out of order.
-      // Use a minimum number of additional streams, or a percentage increase,
-      // whichever is larger.
-      max_streams =
-          max(max_streams + kMaxStreamsMinimumIncrement,
-              static_cast<uint32>(max_streams * kMaxStreamsMultiplier));
-    }
-    set_max_open_streams(max_streams);
+  uint32 max_streams = config_.MaxStreamsPerConnection();
+  if (is_server()) {
+    // A server should accept a small number of additional streams beyond the
+    // limit sent to the client. This helps avoid early connection termination
+    // when FIN/RSTs for old streams are lost or arrive out of order.
+    // Use a minimum number of additional streams, or a percentage increase,
+    // whichever is larger.
+    max_streams =
+        max(max_streams + kMaxStreamsMinimumIncrement,
+            static_cast<uint32>(max_streams * kMaxStreamsMultiplier));
   }
+  set_max_open_streams(max_streams);
 
   if (version == QUIC_VERSION_19) {
     // QUIC_VERSION_19 doesn't support independent stream/session flow
@@ -486,7 +483,8 @@ void QuicSession::OnConfigNegotiated() {
     if (config_.HasReceivedInitialFlowControlWindowBytes()) {
       // Streams which were created before the SHLO was received (0-RTT
       // requests) are now informed of the peer's initial flow control window.
-      uint32 new_window = config_.ReceivedInitialFlowControlWindowBytes();
+      QuicStreamOffset new_window =
+          config_.ReceivedInitialFlowControlWindowBytes();
       OnNewStreamFlowControlWindow(new_window);
       OnNewSessionFlowControlWindow(new_window);
     }
@@ -508,7 +506,7 @@ void QuicSession::OnConfigNegotiated() {
   }
 }
 
-void QuicSession::OnNewStreamFlowControlWindow(uint32 new_window) {
+void QuicSession::OnNewStreamFlowControlWindow(QuicStreamOffset new_window) {
   if (new_window < kDefaultFlowControlSendWindow) {
     LOG(ERROR)
         << "Peer sent us an invalid stream flow control send window: "
@@ -530,7 +528,7 @@ void QuicSession::OnNewStreamFlowControlWindow(uint32 new_window) {
   }
 }
 
-void QuicSession::OnNewSessionFlowControlWindow(uint32 new_window) {
+void QuicSession::OnNewSessionFlowControlWindow(QuicStreamOffset new_window) {
   if (new_window < kDefaultFlowControlSendWindow) {
     LOG(ERROR)
         << "Peer sent us an invalid session flow control send window: "
@@ -563,9 +561,6 @@ void QuicSession::OnCryptoHandshakeEvent(CryptoHandshakeEvent event) {
       // Discard originally encrypted packets, since they can't be decrypted by
       // the peer.
       connection_->NeuterUnencryptedPackets();
-      if (!FLAGS_quic_allow_more_open_streams) {
-        max_open_streams_ = config_.MaxStreamsPerConnection();
-      }
       break;
 
     default: