Avoids the "re-encode HPACK as SPDY3" step.

net/quic/quic_chromium_client_stream.h

Index: net/quic/quic_chromium_client_stream.h
diff --git a/net/quic/quic_chromium_client_stream.h b/net/quic/quic_chromium_client_stream.h
index 857e3c6dd9395f3cc8beaafb5c0d94c57eed36b6..de4a2f5b1c18dd3fd61e6ef67aa3d52ff2e64458 100644
--- a/net/quic/quic_chromium_client_stream.h
+++ b/net/quic/quic_chromium_client_stream.h
@@ -65,6 +65,12 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
 
   // QuicSpdyStream
   void OnStreamHeadersComplete(bool fin, size_t frame_len) override;
+  void OnInitialHeadersComplete(bool fin,
+                                size_t frame_len,
+                                const QuicHeaderList& header_list) override;
+  void OnTrailingHeadersComplete(bool fin,
+                                 size_t frame_len,
+                                 const QuicHeaderList& header_list) override;
   void OnPromiseHeadersComplete(QuicStreamId promised_stream_id,
                                 size_t frame_len) override;
   void OnDataAvailable() override;