Add atomic utilities: AtomicValue, AtomicEnumSet, and AtomicEnumFlag

BUILD.gn

 # 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.
 
 import("//build/config/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/mips.gni")
 
 # Because standalone V8 builds are not supported, assume this is part of a
 # Chromium build.
@@ skipping 643 matching lines @@
     "src/ast-expression-visitor.cc",
     "src/ast-expression-visitor.h",
     "src/ast-literal-reindexer.cc",
     "src/ast-literal-reindexer.h",
     "src/ast-numbering.cc",
     "src/ast-numbering.h",
     "src/ast-value-factory.cc",
     "src/ast-value-factory.h",
     "src/ast.cc",
     "src/ast.h",
+    "src/atomic-utils.h",
     "src/background-parsing-task.cc",
     "src/background-parsing-task.h",
     "src/bailout-reason.cc",
     "src/bailout-reason.h",
     "src/basic-block-profiler.cc",
     "src/basic-block-profiler.h",
     "src/bignum-dtoa.cc",
     "src/bignum-dtoa.h",
     "src/bignum.cc",
     "src/bignum.h",
@@ skipping 1164 matching lines @@
     if (!is_component_build) {
       sources += [
         "$target_gen_dir/d8-js.cc",
       ]
     }
     if (v8_enable_i18n_support) {
       deps += [ "//third_party/icu" ]
     }
   }
 }