Add Object::IsNullOrUndefined(Isolate*) helper method

src/bootstrapper.cc

 // Copyright 2014 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.
 
 #include "src/bootstrapper.h"
 
 #include "src/accessors.h"
 #include "src/api-natives.h"
 #include "src/base/ieee754.h"
 #include "src/code-stubs.h"
@@ skipping 317 matching lines @@
     MaybeHandle<JSGlobalProxy> maybe_global_proxy,
     v8::Local<v8::ObjectTemplate> global_proxy_template) {
   HandleScope scope(isolate_);
   Genesis genesis(isolate_, maybe_global_proxy, global_proxy_template);
   Handle<JSGlobalProxy> global_proxy = genesis.global_proxy();
   if (global_proxy.is_null()) return Handle<JSGlobalProxy>();
   return scope.CloseAndEscape(global_proxy);
 }
 
 void Bootstrapper::DetachGlobal(Handle<Context> env) {
-  env->GetIsolate()->counters()->errors_thrown_per_context()->AddSample(
-    env->GetErrorsThrown());
+  Isolate* isolate = env->GetIsolate();
+  isolate->counters()->errors_thrown_per_context()->AddSample(
+      env->GetErrorsThrown());
 
-  Factory* factory = env->GetIsolate()->factory();
+  Heap* heap = isolate->heap();
   Handle<JSGlobalProxy> global_proxy(JSGlobalProxy::cast(env->global_proxy()));
-  global_proxy->set_native_context(*factory->null_value());
-  JSObject::ForceSetPrototype(global_proxy, factory->null_value());
-  global_proxy->map()->SetConstructor(*factory->null_value());
+  global_proxy->set_native_context(heap->null_value());
+  JSObject::ForceSetPrototype(global_proxy, isolate->factory()->null_value());
+  global_proxy->map()->SetConstructor(heap->null_value());
   if (FLAG_track_detached_contexts) {
     env->GetIsolate()->AddDetachedContext(env);
   }
 }
 
 namespace {
 
 void InstallFunction(Handle<JSObject> target, Handle<Name> property_name,
                      Handle<JSFunction> function, Handle<String> function_name,
                      PropertyAttributes attributes = DONT_ENUM) {
@@ skipping 4385 matching lines @@
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   DCHECK(!IsActive());
 }
 
 }  // namespace internal
 }  // namespace v8