[d8] Use ValueSerializer for postMessage (instead of ad-hoc serializer)

src/value-serializer.h

Index: src/value-serializer.h
diff --git a/src/value-serializer.h b/src/value-serializer.h
index 1ed9457b779033cc8e0ed3e5074c544f800131b4..d300e39aa715035519c28e779867538602fa9f45 100644
--- a/src/value-serializer.h
+++ b/src/value-serializer.h
@@ -86,7 +86,7 @@ class ValueSerializer {
 
  private:
   // Managing allocations of the internal buffer.
-  void ExpandBuffer(size_t required_capacity);
+  Maybe<bool> ExpandBuffer(size_t required_capacity);
 
   // Writing the wire format.
   void WriteTag(SerializationTag tag);
@@ -96,7 +96,7 @@ class ValueSerializer {
   void WriteZigZag(T value);
   void WriteOneByteString(Vector<const uint8_t> chars);
   void WriteTwoByteString(Vector<const uc16> chars);
-  uint8_t* ReserveRawBytes(size_t bytes);
+  Maybe<uint8_t*> ReserveRawBytes(size_t bytes);
 
   // Writing V8 objects of various kinds.
   void WriteOddball(Oddball* oddball);
@@ -134,11 +134,14 @@ class ValueSerializer {
   V8_NOINLINE void ThrowDataCloneError(MessageTemplate::Template template_index,
                                        Handle<Object> arg0);
 
+  Maybe<bool> ThrowIfOutOfMemory();
+
   Isolate* const isolate_;
   v8::ValueSerializer::Delegate* const delegate_;
   uint8_t* buffer_ = nullptr;
   size_t buffer_size_ = 0;
   size_t buffer_capacity_ = 0;
+  bool out_of_memory_ = false;
   Zone zone_;
 
   // To avoid extra lookups in the identity map, ID+1 is actually stored in the