ValueSerializer: Expose reading/writing doubles to embedder.

src/value-serializer.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/value-serializer.h"
 
 #include <type_traits>
 
 #include "src/base/logging.h"
 #include "src/conversions.h"
@@ skipping 885 matching lines @@
 }
 
 bool ValueDeserializer::ReadUint32(uint32_t* value) {
   return ReadVarint<uint32_t>().To(value);
 }
 
 bool ValueDeserializer::ReadUint64(uint64_t* value) {
   return ReadVarint<uint64_t>().To(value);
 }
 
+bool ValueDeserializer::ReadDouble(double* value) {
+  return ReadDouble().To(value);
+}
+
 bool ValueDeserializer::ReadRawBytes(size_t length, const void** data) {
   if (length > static_cast<size_t>(end_ - position_)) return false;
   *data = position_;
   position_ += length;
   return true;
 }
 
 void ValueDeserializer::TransferArrayBuffer(
     uint32_t transfer_id, Handle<JSArrayBuffer> array_buffer) {
   if (array_buffer_transfer_map_.is_null()) {
@@ skipping 796 matching lines @@
   if (stack.size() != 1) {
     isolate_->Throw(*isolate_->factory()->NewError(
         MessageTemplate::kDataCloneDeserializationError));
     return MaybeHandle<Object>();
   }
   return scope.CloseAndEscape(stack[0]);
 }
 
 }  // namespace internal
 }  // namespace v8