Move QuicIoVector into its own header file. No behavior change.

net/quic/test_tools/quic_packet_creator_peer.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_QUIC_TEST_TOOLS_QUIC_PACKET_CREATOR_PEER_H_
 #define NET_QUIC_TEST_TOOLS_QUIC_PACKET_CREATOR_PEER_H_
 
 #include <stddef.h>
 
 #include "base/macros.h"
+#include "net/quic/core/quic_iovector.h"
 #include "net/quic/core/quic_protocol.h"
 
 namespace net {
 class QuicPacketCreator;
 
 namespace test {
 
 class QuicPacketCreatorPeer {
  public:
   static bool SendVersionInPacket(QuicPacketCreator* creator);
@@ skipping 27 matching lines @@
 
  private:
   DISALLOW_COPY_AND_ASSIGN(QuicPacketCreatorPeer);
 };
 
 }  // namespace test
 
 }  // namespace net
 
 #endif  // NET_QUIC_TEST_TOOLS_QUIC_PACKET_CREATOR_PEER_H_