Revert of Create libsampler as V8 sampler library.

src/libsampler/utils.h

-// Copyright 2016 the V8 project 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 V8_LIBSAMPLER_UTILS_H_
-#define V8_LIBSAMPLER_UTILS_H_
-
-#include "include/v8.h"
-
-namespace v8 {
-namespace sampler {
-
-class Malloced {
- public:
-  static void* New(size_t size) {
-    return malloc(size);
-  }
-
-  static void Delete(void* p) {
-    free(p);
-  }
-};
-
-}  // namespace sampler
-}  // namespace v8
-
-#endif  // V8_LIBSAMPLER_UTILS_H_