Unify LookupIterator::GetRoot and Objects::GetRootMap

src/lookup.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/v8.h"
 
 #include "src/bootstrapper.h"
 #include "src/lookup.h"
 
 namespace v8 {
 namespace internal {
 
 
 void LookupIterator::Next() {
   has_property_ = false;
   do {
     state_ = LookupInHolder();
   } while (!IsFound() && NextHolder());
 }
 
 
 Handle<JSReceiver> LookupIterator::GetRoot() const {
   Handle<Object> receiver = GetReceiver();
   if (receiver->IsJSReceiver()) return Handle<JSReceiver>::cast(receiver);
-  Context* native_context = isolate_->context()->native_context();
-  JSFunction* function;
-  if (receiver->IsNumber()) {
-    function = native_context->number_function();
-  } else if (receiver->IsString()) {
-    function = native_context->string_function();
-  } else if (receiver->IsSymbol()) {
-    function = native_context->symbol_function();
-  } else if (receiver->IsBoolean()) {
-    function = native_context->boolean_function();
-  } else {
-    UNREACHABLE();
-    function = NULL;
-  }
-  return handle(JSReceiver::cast(function->instance_prototype()));
+  Handle<Object> root =
+      handle(receiver->GetRootMap(isolate_)->prototype(), isolate_);
+  CHECK(!root->IsNull());
+  return Handle<JSReceiver>::cast(root);
 }
 
 
 Handle<Map> LookupIterator::GetReceiverMap() const {
   Handle<Object> receiver = GetReceiver();
   if (receiver->IsNumber()) return isolate_->factory()->heap_number_map();
   return handle(Handle<HeapObject>::cast(receiver)->map());
 }
 
 
@@ skipping 141 matching lines @@
   Handle<Object> value = FetchValue();
   if (value->IsTheHole()) {
     ASSERT(property_details_.IsReadOnly());
     return factory()->undefined_value();
   }
   return value;
 }
 
 
 } }  // namespace v8::internal