Split Dictionary's get and convert into DictionaryHelper.

Source/bindings/core/v8/v8.gypi

 # 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.
 
 {
     'includes': [
         'custom/custom.gypi',
         '../../modules/v8/generated.gypi',
     ],
     'variables': {
@@ skipping 13 matching lines @@
             'CustomElementConstructorBuilder.h',
             'CustomElementWrapper.cpp',
             'CustomElementWrapper.h',
             'DOMDataStore.cpp',
             'DOMDataStore.h',
             'DOMWrapperMap.h',
             'DOMWrapperWorld.cpp',
             'DOMWrapperWorld.h',
             'Dictionary.cpp',
             'Dictionary.h',
+            'DictionaryHelperForBindings.h',
+            'DictionaryHelperForCore.cpp',
             'ExceptionMessages.cpp',
             'ExceptionMessages.h',
             'ExceptionState.cpp',
             'ExceptionState.h',
             'ExceptionStatePlaceholder.cpp',
             'ExceptionStatePlaceholder.h',
             'ModuleProxy.cpp',
             'ModuleProxy.h',
             'NPV8Object.cpp',
             'NPV8Object.h',
@@ skipping 114 matching lines @@
             'npruntime.cpp',
             'npruntime_impl.h',
             'npruntime_priv.h',
         ],
         'bindings_core_v8_unittest_files': [
             'ScriptPromiseTest.cpp',
             'ScriptPromisePropertyTest.cpp',
         ],
     },
 }