Add QuicStringPiece which is actually StringPiece.

net/quic/test_tools/fake_proof_source.h

 // Copyright (c) 2016 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_FAKE_PROOF_SOURCE_H_
 #define NET_QUIC_TEST_TOOLS_FAKE_PROOF_SOURCE_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "net/quic/core/crypto/proof_source.h"
+#include "net/quic/platform/api/quic_string_piece.h"
 
 namespace net {
 namespace test {
 
 // Implementation of ProofSource which delegates to a ProofSourceForTesting,
 // except that when the async GetProof is called, it captures the call and
 // allows tests to see that a call is pending, which they can then cause to
 // complete at a time of their choosing.
 class FakeProofSource : public ProofSource {
  public:
   FakeProofSource();
   ~FakeProofSource() override;
 
   // Before this object is "active", all calls to GetProof will be delegated
   // immediately.  Once "active", the async ones will be intercepted.  This
   // distinction is necessary to ensure that GetProof can be called without
   // interference during test case setup.
   void Activate();
 
   // ProofSource interface
   void GetProof(const QuicSocketAddress& server_address,
                 const std::string& hostname,
                 const std::string& server_config,
                 QuicVersion quic_version,
-                base::StringPiece chlo_hash,
+                QuicStringPiece chlo_hash,
                 const QuicTagVector& connection_options,
                 std::unique_ptr<ProofSource::Callback> callback) override;
 
   // Get the number of callbacks which are pending
   int NumPendingCallbacks() const;
 
   // Invoke a pending callback.  The index refers to the position in params_ of
   // the callback to be completed.
   void InvokePendingCallback(int n);
 
@@ skipping 22 matching lines @@
     std::unique_ptr<ProofSource::Callback> callback;
   };
 
   std::vector<Params> params_;
 };
 
 }  // namespace test
 }  // namespace net
 
 #endif  // NET_QUIC_TEST_TOOLS_FAKE_PROOF_SOURCE_H_