Revert of Add the concept of a V8 extras exports object (patchset #5 id:80001...

Revert of Add the concept of a V8 extras exports object (patchset #5 id:80001 of https://codereview.chromium.org/1128113006/)

Reason for revert:
[Sheriff] Causes gc stress failures:
http://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20arm64%20-%20sim%20-%20gc%20stress/builds/2167

Original issue's description:
> Add the concept of a V8 extras exports object
>
> Exposed to the extras as extrasExports (on the builtins object), on
> which they can put things that should be accessible from C++. Exposed
> to C++ through the V8 API as v8::Context::GetExtrasExportsObject().
>
> Adding a test (in test-api.cc) required adding a simple extra,
> test-extra.js, which we build into the standalone builds.
>
> R=yangguo@chromium.org, jochen@chromium.org
> BUG=
>
> Committed: https://crrev.com/ad547cea05f3e02c67243b682e933fc53ac763d9
> Cr-Commit-Position: refs/heads/master@{#28317}

TBR=jochen@chromium.org,yangguo@chromium.org,domenic@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/1127313005

Cr-Commit-Position: refs/heads/master@{#28332}

build/standalone.gypi

@@ -100,9 +100,6 @@
     'msan%': '<(msan)',
     'tsan%': '<(tsan)',
 
-    # Add a simple extra solely for the purpose of the cctests
-    'v8_extra_library_files': ['../test/cctest/test-extra.js'],
-
     # .gyp files or targets should set v8_code to 1 if they build V8 specific
     # code, as opposed to external code.  This variable is used to control such
     # things as the set of warnings to enable, and whether warnings are treated

include/v8.h

@@ -6370,12 +6370,6 @@ class V8_EXPORT Context {
    */
   V8_INLINE Local<Value> GetEmbedderData(int index);
 
-  /**
-   * Gets the exports object used by V8 extras. Extra natives get a reference
-   * to this object and can use it to export functionality.
-   */
-  Local<Object> GetExtrasExportsObject();
-
   /**
    * Sets the embedder data with the given index, growing the data as
    * needed. Note that index 0 currently has a special meaning for Chrome's

src/api.cc

@@ -5492,14 +5492,6 @@ void Context::DetachGlobal() {
 }
 
 
-Local<v8::Object> Context::GetExtrasExportsObject() {
-  i::Handle<i::Context> context = Utils::OpenHandle(this);
-  i::Isolate* isolate = context->GetIsolate();
-  i::Handle<i::JSObject> exports(context->extras_exports_object(), isolate);
-  return Utils::ToLocal(exports);
-}
-
-
 void Context::AllowCodeGenerationFromStrings(bool allow) {
   i::Handle<i::Context> context = Utils::OpenHandle(this);
   i::Isolate* isolate = context->GetIsolate();

src/bootstrapper.cc

@@ -201,7 +201,6 @@ class Genesis BASE_EMBEDDED {
   void InitializeGlobal(Handle<GlobalObject> global_object,
                         Handle<JSFunction> empty_function);
   void InitializeExperimentalGlobal();
-  void InitializeExtrasExportsObject();
   // Installs the contents of the native .js files on the global objects.
   // Used for creating a context from scratch.
   void InstallNativeFunctions();
@@ -1442,20 +1441,6 @@ void Genesis::InitializeExperimentalGlobal() {
 }
 
 
-void Genesis::InitializeExtrasExportsObject() {
-  Handle<JSObject> exports =
-      factory()->NewJSObject(isolate()->object_function(), TENURED);
-
-  native_context()->set_extras_exports_object(*exports);
-
-  Handle<JSBuiltinsObject> builtins(native_context()->builtins());
-  Handle<String> exports_string =
-      factory()->InternalizeOneByteString(STATIC_CHAR_VECTOR("extrasExports"));
-  Runtime::SetObjectProperty(isolate(), builtins, exports_string, exports,
-                             STRICT).Assert();
-}
-
-
 bool Genesis::CompileBuiltin(Isolate* isolate, int index) {
   Vector<const char> name = Natives::GetScriptName(index);
   Handle<String> source_code =
@@ -2984,7 +2969,6 @@ Genesis::Genesis(Isolate* isolate,
   // them after they have already been deserialized would also fail.
   if (!isolate->serializer_enabled()) {
     InitializeExperimentalGlobal();
-    InitializeExtrasExportsObject();
     if (!InstallExperimentalNatives()) return;
     if (!InstallExtraNatives()) return;
   }

src/contexts.h

@@ -185,8 +185,7 @@ enum BindingFlags {
   V(MAP_ITERATOR_MAP_INDEX, Map, map_iterator_map)                             \
   V(SET_ITERATOR_MAP_INDEX, Map, set_iterator_map)                             \
   V(ARRAY_VALUES_ITERATOR_INDEX, JSFunction, array_values_iterator)            \
-  V(SCRIPT_CONTEXT_TABLE_INDEX, ScriptContextTable, script_context_table)      \
-  V(EXTRAS_EXPORTS_OBJECT_INDEX, JSObject, extras_exports_object)
+  V(SCRIPT_CONTEXT_TABLE_INDEX, ScriptContextTable, script_context_table)
 
 
 // A table of all script contexts. Every loaded top-level script with top-level
@@ -423,7 +422,6 @@ class Context: public FixedArray {
     SCRIPT_CONTEXT_TABLE_INDEX,
     MAP_CACHE_INDEX,
     TO_LENGTH_FUN_INDEX,
-    EXTRAS_EXPORTS_OBJECT_INDEX,
 
     // Properties from here are treated as weak references by the full GC.
     // Scavenge treats them as strong references.

src/runtime/runtime-test.cc

@@ -364,12 +364,6 @@ RUNTIME_FUNCTION(Runtime_NativeScriptsCount) {
 }
 
 
-RUNTIME_FUNCTION(Runtime_NativeExtrasCount) {
-  DCHECK(args.length() == 0);
-  return Smi::FromInt(ExtraNatives::GetBuiltinsCount());
-}
-
-
 // Returns V8 version as a string.
 RUNTIME_FUNCTION(Runtime_GetV8Version) {
   HandleScope scope(isolate);

src/runtime/runtime.h

@@ -592,7 +592,6 @@ namespace internal {
   F(Abort, 1, 1)                              \
   F(AbortJS, 1, 1)                            \
   F(NativeScriptsCount, 0, 1)                 \
-  F(NativeExtrasCount, 0, 1)                  \
   F(GetV8Version, 0, 1)                       \
   F(DisassembleFunction, 1, 1)                \
   F(TraceEnter, 0, 1)                         \

test/cctest/test-api.cc

@@ -21029,21 +21029,3 @@ TEST(SealHandleScopeNested) {
     USE(obj);
   }
 }
-
-
-TEST(ExtrasExportsObject) {
-  v8::Isolate* isolate = CcTest::isolate();
-  v8::HandleScope handle_scope(isolate);
-  LocalContext env;
-
-  // standalone.gypi ensures we include the test-extra.js file, which should
-  // add the testExtraShouldReturnFive export
-  v8::Local<v8::Object> exports = env->GetExtrasExportsObject();
-
-  auto func =
-      exports->Get(v8_str("testExtraShouldReturnFive")).As<v8::Function>();
-  auto undefined = v8::Undefined(isolate);
-  auto result = func->Call(undefined, 0, {}).As<v8::Number>();
-
-  CHECK(result->Value() == 5.0);
-}

test/cctest/test-extra.js

-// Copyright 2015 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.
-
-(function () {
-
-  'use strict';
-
-  extrasExports.testExtraShouldReturnFive = function () {
-    return 5;
-  };
-
-});

test/mjsunit/debug-script.js

@@ -66,7 +66,7 @@ for (i = 0; i < scripts.length; i++) {
 }
 
 // This has to be updated if the number of native scripts change.
-assertEquals(%NativeScriptsCount() + %NativeExtrasCount(), named_native_count);
+assertEquals(%NativeScriptsCount(), named_native_count);
 // Only the 'gc' extension is loaded.
 assertEquals(1, extension_count);
 // This script and mjsunit.js has been loaded.  If using d8, d8 loads