Cancel pending retransmissions which are greater than the largest newly acked packet when using the…

net/quic/quic_protocol.h

Index: net/quic/quic_protocol.h
diff --git a/net/quic/quic_protocol.h b/net/quic/quic_protocol.h
index 6cdb496aaabc058b192015b05e404715c3e72b3e..678b4581896515199f2b9ce7a68d6dae887d2b2d 100644
--- a/net/quic/quic_protocol.h
+++ b/net/quic/quic_protocol.h
@@ -1442,7 +1442,9 @@ struct NET_EXPORT_PRIVATE TransmissionInfo {
   TransmissionType transmission_type;
   // In flight packets have not been abandoned or lost.
   bool in_flight;
-  // True if the packet can never be acked, so it can be removed.
+  // True if the packet can never be acked, so it can be removed.  Occurs when
+  // a packet is never sent, after it is acknowledged once, or if it's a crypto
+  // packet we never expect to receive an ack for.
   bool is_unackable;
   // True if the packet contains stream data from the crypto stream.
   bool has_crypto_handshake;