[es6] Fix invalid ToString in implementation of ToName.

src/full-codegen/x64/full-codegen-x64.cc

 // Copyright 2012 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.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/compiler.h"
@@ skipping 3683 matching lines @@
   // Load the argument into rax and convert it.
   VisitForAccumulatorValue(args->at(0));
 
   // Convert the object to a name.
   Label convert, done_convert;
   __ JumpIfSmi(rax, &convert, Label::kNear);
   STATIC_ASSERT(FIRST_NAME_TYPE == FIRST_TYPE);
   __ CmpObjectType(rax, LAST_NAME_TYPE, rcx);
   __ j(below_equal, &done_convert, Label::kNear);
   __ bind(&convert);
-  ToStringStub stub(isolate());
-  __ CallStub(&stub);
+  __ Push(rax);
+  __ CallRuntime(Runtime::kToName, 1);
   __ bind(&done_convert);
   context()->Plug(rax);
 }
 
 
 void FullCodeGenerator::EmitToObject(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK_EQ(1, args->length());
 
   // Load the argument into rax and convert it.
@@ skipping 1426 matching lines @@
             Assembler::target_address_at(call_target_address,
                                          unoptimized_code));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64