Reduce SpdyHeaderBlock copies with move semantics in shared code.

net/tools/quic/quic_spdy_client_stream.cc

Index: net/tools/quic/quic_spdy_client_stream.cc
diff --git a/net/tools/quic/quic_spdy_client_stream.cc b/net/tools/quic/quic_spdy_client_stream.cc
index 633963ae8ece7226d5928fc30f8f4b31e46b1740..becb6a6ed37e8132755ce6966597a13201748133 100644
--- a/net/tools/quic/quic_spdy_client_stream.cc
+++ b/net/tools/quic/quic_spdy_client_stream.cc
@@ -4,6 +4,8 @@
 
 #include "net/tools/quic/quic_spdy_client_stream.h"
 
+#include <utility>
+
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
@@ -180,12 +182,13 @@ void QuicSpdyClientStream::OnDataAvailable() {
   }
 }
 
-size_t QuicSpdyClientStream::SendRequest(const SpdyHeaderBlock& headers,
+size_t QuicSpdyClientStream::SendRequest(SpdyHeaderBlock headers,
                                          StringPiece body,
                                          bool fin) {
   bool send_fin_with_headers = fin && body.empty();
   size_t bytes_sent = body.size();
-  header_bytes_written_ = WriteHeaders(headers, send_fin_with_headers, nullptr);
+  header_bytes_written_ =
+      WriteHeaders(std::move(headers), send_fin_with_headers, nullptr);
   bytes_sent += header_bytes_written_;
 
   if (!body.empty()) {