Remove some duplicate code in quic tests.

net/quic/test_tools/quic_test_utils.cc

Index: net/quic/test_tools/quic_test_utils.cc
diff --git a/net/quic/test_tools/quic_test_utils.cc b/net/quic/test_tools/quic_test_utils.cc
index dd415264d6e4fa704b5f0a7b27814c552cb0c7f6..34de8935426ecd1473b0909008374260b7a7930b 100644
--- a/net/quic/test_tools/quic_test_utils.cc
+++ b/net/quic/test_tools/quic_test_utils.cc
@@ -5,6 +5,7 @@
 #include "net/quic/test_tools/quic_test_utils.h"
 
 #include "base/stl_util.h"
+#include "base/strings/string_number_conversions.h"
 #include "net/quic/crypto/crypto_framer.h"
 #include "net/quic/crypto/crypto_handshake.h"
 #include "net/quic/crypto/crypto_utils.h"
@@ -386,6 +387,18 @@ void CompareCharArraysWithHexError(
       << HexDumpWithMarks(actual, actual_len, marks.get(), max_len);
 }
 
+bool DecodeHexString(const base::StringPiece& hex, std::string* bytes) {
+  *bytes = string();

[wtc, 2013/11/04 01:58:27]

Nit: would bytes->clear() be better?

[eroman, 2013/11/04 19:39:58]

Done.

+  if (hex.empty())
+    return true;
+  std::vector<uint8> v;
+  if (!base::HexStringToBytes(hex.as_string(), &v))
+    return false;
+  if (!v.empty())
+    *bytes = string(reinterpret_cast<const char*>(&v[0]), v.size());

[wtc, 2013/11/04 01:58:27]

Nit: this probably can be a bytes->append() call.

It is s shame we have to copy from a vector to a string.

[eroman, 2013/11/04 19:39:58]

Done (using assign()).

+  return true;
+}
+
 static QuicPacket* ConstructPacketFromHandshakeMessage(
     QuicGuid guid,
     const CryptoHandshakeMessage& message,