V8ObjectBuilder::addString support Nullable.

third_party/WebKit/Source/bindings/core/v8/V8ObjectBuilder.cpp

 // Copyright 2015 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.
 
 #include "bindings/core/v8/V8ObjectBuilder.h"
 
 #include "bindings/core/v8/V8Binding.h"
 
 namespace blink {
 
@@ skipping 17 matching lines @@
                           : v8::False(m_scriptState->isolate()));
   return *this;
 }
 
 V8ObjectBuilder& V8ObjectBuilder::addNumber(const String& name, double value) {
   addInternal(name, v8::Number::New(m_scriptState->isolate(), value));
   return *this;
 }
 
 V8ObjectBuilder& V8ObjectBuilder::addString(const String& name,
-                                            const String& value) {
-  addInternal(name, v8String(m_scriptState->isolate(), value));
+                                            const String& value,
+                                            bool isNullable) {
+  if (isNullable && value.isNull()) {
+    addInternal(name, v8::Null(m_scriptState->isolate()));
+  } else {
+    addInternal(name, v8String(m_scriptState->isolate(), value));
+  }
   return *this;
 }
 
 ScriptValue V8ObjectBuilder::scriptValue() const {
   return ScriptValue(m_scriptState.get(), m_object);
 }
 
 void V8ObjectBuilder::addInternal(const String& name,
                                   v8::Local<v8::Value> value) {
   if (m_object.IsEmpty())
     return;
   if (value.IsEmpty() ||
       m_object
           ->CreateDataProperty(m_scriptState->context(),
                                v8String(m_scriptState->isolate(), name), value)
           .IsNothing())
     m_object.Clear();
 }
 
 }  // namespace blink