Remove Sync JS generic request/reply framework

sync/js/js_arg_list.h

-// Copyright 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.
-
-#ifndef SYNC_JS_JS_ARG_LIST_H_
-#define SYNC_JS_JS_ARG_LIST_H_
-
-// See README.js for design comments.
-
-#include <string>
-
-#include "base/values.h"
-#include "sync/base/sync_export.h"
-#include "sync/internal_api/public/util/immutable.h"
-
-namespace syncer {
-
-// A thin wrapper around Immutable<ListValue>.  Used for passing
-// around argument lists to different threads.
-class SYNC_EXPORT JsArgList {
- public:
-  // Uses an empty argument list.
-  JsArgList();
-
-  // Takes over the data in |args|, leaving |args| empty.
-  explicit JsArgList(base::ListValue* args);
-
-  ~JsArgList();
-
-  const base::ListValue& Get() const;
-
-  std::string ToString() const;
-
-  // Copy constructor and assignment operator welcome.
-
- private:
-  typedef Immutable<base::ListValue, HasSwapMemFnByPtr<base::ListValue> >
-      ImmutableListValue;
-  ImmutableListValue args_;
-};
-
-}  // namespace syncer
-
-#endif  // SYNC_JS_JS_ARG_LIST_H_