EDK: Convert remaining scoped_ptr -> std::unique_ptr in //mojo/edk/system.

mojo/edk/system/message_in_transit_test_utils.h

 // Copyright 2015 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 MOJO_EDK_SYSTEM_MESSAGE_IN_TRANSIT_TEST_UTILS_H_
 #define MOJO_EDK_SYSTEM_MESSAGE_IN_TRANSIT_TEST_UTILS_H_
 
-#include "base/memory/scoped_ptr.h"
+#include <memory>
+
 #include "mojo/edk/system/message_in_transit.h"
 
 namespace mojo {
 namespace system {
 namespace test {
 
 // Makes a test message. It will be of type
 // |MessageInTransit::Type::ENDPOINT_CLIENT| and subtype
 // |MessageInTransit::Subtype::ENDPOINT_CLIENT_DATA|, and contain data
 // associated with |id| (so that test messages with different |id|s are
 // distinguishable).
-scoped_ptr<MessageInTransit> MakeTestMessage(unsigned id);
+std::unique_ptr<MessageInTransit> MakeTestMessage(unsigned id);
 
 // Verifies a test message: ASSERTs that |message| is non-null, and EXPECTs that
 // it looks like a message created using |MakeTestMessage(id)| (see above).
 void VerifyTestMessage(const MessageInTransit* message, unsigned id);
 
 // Checks if |message| looks like a test message created using
 // |MakeTestMessage()|, in which case it returns true and sets |*id|. (Otherwise
 // it returns false and leaves |*id| alone.)
 bool IsTestMessage(MessageInTransit* message, unsigned* id);
 
 }  // namespace test
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_MESSAGE_IN_TRANSIT_TEST_UTILS_H_