Mojo: Convert MemoryTest.Valid to the new user pointer handling (see r285350).

mojo/system/entrypoints.cc

 // Copyright 2014 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 "mojo/system/entrypoints.h"
 
 #include "mojo/public/c/system/buffer.h"
 #include "mojo/public/c/system/data_pipe.h"
 #include "mojo/public/c/system/functions.h"
 #include "mojo/public/c/system/message_pipe.h"
 #include "mojo/system/core.h"
 
 static mojo::system::Core* g_core = NULL;
 
 using mojo::system::MakeUserPointer;
-using mojo::system::MakeUserPointerValue;
 
 namespace mojo {
 namespace system {
 namespace entrypoints {
 
 void SetCore(Core* core) {
   g_core = core;
 }
 
 Core* GetCore() {
@@ skipping 149 matching lines @@
                          void** buffer,
                          MojoMapBufferFlags flags) {
   return g_core->MapBuffer(buffer_handle,
                            offset,
                            num_bytes,
                            MakeUserPointer(buffer),
                            flags);
 }
 
 MojoResult MojoUnmapBuffer(void* buffer) {
-  return g_core->UnmapBuffer(MakeUserPointerValue(buffer));
+  return g_core->UnmapBuffer(MakeUserPointer(buffer));
 }
 
 }  // extern "C"