Part of QUIC v39 change: 1) do not ack acks. 2) Send a WINDOW_UPDATE frame every 20 packets which d…

net/quic/core/quic_session.cc

Index: net/quic/core/quic_session.cc
diff --git a/net/quic/core/quic_session.cc b/net/quic/core/quic_session.cc
index 241f29290e11be3ef6a9a2e37cff2869bb2aa1dc..9cda039a97ec7484052838b7ddbecdbcbf005c48 100644
--- a/net/quic/core/quic_session.cc
+++ b/net/quic/core/quic_session.cc
@@ -819,6 +819,10 @@ void QuicSession::PostProcessAfterData() {
   closed_streams_.clear();
 }
 
+void QuicSession::OnAckNeedsRetransmittableFrame() {
+  flow_controller_.SendWindowUpdate();
+}
+
 size_t QuicSession::GetNumDynamicOutgoingStreams() const {
   DCHECK_GE(dynamic_stream_map_.size(), num_dynamic_incoming_streams_);
   return dynamic_stream_map_.size() - num_dynamic_incoming_streams_;