Add QuicStringPiece which is actually StringPiece.

net/quic/test_tools/quic_stream_peer.cc

 // 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.
 
 #include "net/quic/test_tools/quic_stream_peer.h"
 
 #include <list>
 
 #include "net/quic/core/quic_stream.h"
 
-using base::StringPiece;
-
 namespace net {
 namespace test {
 
 // static
 void QuicStreamPeer::SetWriteSideClosed(bool value, QuicStream* stream) {
   stream->write_side_closed_ = value;
 }
 
 // static
 void QuicStreamPeer::SetStreamBytesWritten(
@@ skipping 36 matching lines @@
 
 // static
 bool QuicStreamPeer::StreamContributesToConnectionFlowControl(
     QuicStream* stream) {
   return stream->stream_contributes_to_connection_flow_control_;
 }
 
 // static
 void QuicStreamPeer::WriteOrBufferData(
     QuicStream* stream,
-    StringPiece data,
+    QuicStringPiece data,
     bool fin,
     QuicReferenceCountedPointer<QuicAckListenerInterface> ack_listener) {
   stream->WriteOrBufferData(data, fin, std::move(ack_listener));
 }
 
 // static
 QuicStreamSequencer* QuicStreamPeer::sequencer(QuicStream* stream) {
   return &(stream->sequencer_);
 }
 
 // static
 QuicSession* QuicStreamPeer::session(QuicStream* stream) {
   return stream->session();
 }
 
 }  // namespace test
 }  // namespace net