Add methods for creating V8 extras-based ReadableStreams from C++

Source/core/core_generated.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': [
     '../bindings/core/core.gypi',  # for bindings_core_v8_output_dir
   ],
 
   'variables': {
@@ skipping 33 matching lines @@
       '<(bindings_core_v8_output_dir)/V8InternalSettingsGenerated.cpp',
       '<(bindings_core_v8_output_dir)/V8InternalSettingsGenerated.h',
       '<(bindings_core_v8_output_dir)/V8InternalRuntimeFlags.cpp',
       '<(bindings_core_v8_output_dir)/V8InternalRuntimeFlags.h',
       '<(bindings_core_v8_output_dir)/V8LayerRect.cpp',
       '<(bindings_core_v8_output_dir)/V8LayerRect.h',
       '<(bindings_core_v8_output_dir)/V8LayerRectList.cpp',
       '<(bindings_core_v8_output_dir)/V8LayerRectList.h',
       '<(bindings_core_v8_output_dir)/V8RefCountedScriptWrappable.cpp',
       '<(bindings_core_v8_output_dir)/V8RefCountedScriptWrappable.h',
+      '<(bindings_core_v8_output_dir)/V8ReadableStreamTestRequest.cpp',
+      '<(bindings_core_v8_output_dir)/V8ReadableStreamTestRequest.h',
+      '<(bindings_core_v8_output_dir)/V8ReadableStreamTestSource.cpp',
+      '<(bindings_core_v8_output_dir)/V8ReadableStreamTestSource.h',
+      '<(bindings_core_v8_output_dir)/V8ReadableStreamTestCase.cpp',
+      '<(bindings_core_v8_output_dir)/V8ReadableStreamTestCase.h',
       '<(bindings_core_v8_output_dir)/V8InternalDictionary.cpp',
       '<(bindings_core_v8_output_dir)/V8InternalDictionary.h',
       '<(bindings_core_v8_output_dir)/V8InternalDictionaryDerived.cpp',
       '<(bindings_core_v8_output_dir)/V8InternalDictionaryDerived.h',
       '<(bindings_core_v8_output_dir)/V8PluginPlaceholderOptions.cpp',
       '<(bindings_core_v8_output_dir)/V8PluginPlaceholderOptions.h',
     ],
 
     'generated_core_additional_files': [
       # Additional .cpp files for HashTools.h
@@ skipping 58 matching lines @@
 
       # Generated from make_style_builder.py
       '<(blink_core_output_dir)/StyleBuilder.cpp',
       '<(blink_core_output_dir)/StyleBuilderFunctions.cpp',
 
       # Generated from make_css_property_metadata.py
       '<(blink_core_output_dir)/CSSPropertyMetadata.cpp',
     ],
   },
 }