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

net/quic/core/quic_stream.h

 // Copyright (c) 2012 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.
 //
 // The base class for client/server QUIC streams.
 
 // It does not contain the entire interface needed by an application to interact
 // with a QUIC stream.  Some parts of the interface must be obtained by
 // accessing the owning session object.  A subclass of QuicStream
 // connects the object and the application that generates and consumes the data
@@ skipping 12 matching lines @@
 
 #include <list>
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/string_piece.h"
 #include "net/base/iovec.h"
 #include "net/base/net_export.h"
 #include "net/quic/core/quic_flow_controller.h"
+#include "net/quic/core/quic_iovector.h"
 #include "net/quic/core/quic_protocol.h"
 #include "net/quic/core/quic_stream_sequencer.h"
 #include "net/quic/core/quic_types.h"
 
 namespace net {
 
 namespace test {
 class QuicStreamPeer;
 }  // namespace test
 
@@ skipping 269 matching lines @@
 
   // For debugging only, used for busy loop check.
   size_t busy_counter_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicStream);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CORE_QUIC_STREAM_H_