Update from https://crrev.com/304121

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 afd5ed4c6f7d3cc6e033ef3d220ba0aa4a2ad79a..ad920d0f21028ad3bfca01f9ac35665204d800af 100644
--- a/net/quic/quic_protocol.h
+++ b/net/quic/quic_protocol.h
@@ -76,6 +76,9 @@ const QuicByteCount kDefaultSocketReceiveBuffer = 256 * 1024;
 // Smaller values are ignored.
 const QuicByteCount kMinSocketReceiveBuffer = 16 * 1024;
 
+// Don't allow a client to suggest an RTT shorter than 10ms.
+const uint32 kMinInitialRoundTripTimeUs = 10 * kNumMicrosPerMilli;
+
 // Don't allow a client to suggest an RTT longer than 15 seconds.
 const uint32 kMaxInitialRoundTripTimeUs = 15 * kNumMicrosPerSecond;