Add Object::IsNullOrUndefined(Isolate*) helper method

src/inspector/string-util.cc

 // Copyright 2016 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/inspector/string-util.h"
 
 #include "src/inspector/protocol/Protocol.h"
 
 namespace v8_inspector {
 
@@ skipping 32 matching lines @@
                isolate, reinterpret_cast<const uint8_t*>(string.characters8()),
                v8::NewStringType::kNormal, static_cast<int>(string.length()))
         .ToLocalChecked();
   return v8::String::NewFromTwoByte(
              isolate, reinterpret_cast<const uint16_t*>(string.characters16()),
              v8::NewStringType::kNormal, static_cast<int>(string.length()))
       .ToLocalChecked();
 }
 
 String16 toProtocolString(v8::Local<v8::String> value) {
-  if (value.IsEmpty() || value->IsNull() || value->IsUndefined())
-    return String16();
+  if (value.IsEmpty() || value->IsNullOrUndefined()) return String16();
   std::unique_ptr<UChar[]> buffer(new UChar[value->Length()]);
   value->Write(reinterpret_cast<uint16_t*>(buffer.get()), 0, value->Length());
   return String16(buffer.get(), value->Length());
 }
 
 String16 toProtocolStringWithTypeCheck(v8::Local<v8::Value> value) {
   if (value.IsEmpty() || !value->IsString()) return String16();
   return toProtocolString(value.As<v8::String>());
 }
 
@@ skipping 57 matching lines @@
 std::unique_ptr<StringBufferImpl> StringBufferImpl::adopt(String16& string) {
   return std::unique_ptr<StringBufferImpl>(new StringBufferImpl(string));
 }
 
 StringBufferImpl::StringBufferImpl(String16& string) {
   m_owner.swap(string);
   m_string = toStringView(m_owner);
 }
 
 }  // namespace v8_inspector