Remove mojo::system::Mutex's use of base::internal::LockImpl.

mojo/edk/embedder/system_impl_private_entrypoints.cc

 // 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.
 
+#include "base/logging.h"
 #include "mojo/edk/embedder/embedder_internal.h"
 #include "mojo/edk/system/core.h"
 #include "mojo/edk/system/dispatcher.h"
 #include "mojo/edk/system/ref_ptr.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/public/platform/native/system_impl_private.h"
 
@@ skipping 238 matching lines @@
                          MakeUserPointer(buffer), flags);
 }
 
 MojoResult MojoSystemImplUnmapBuffer(MojoSystemImpl system, void* buffer) {
   mojo::system::Core* core = static_cast<mojo::system::Core*>(system);
   DCHECK(core);
   return core->UnmapBuffer(MakeUserPointer(buffer));
 }
 
 }  // extern "C"