[objects] do not visit ArrayBuffer's backing store

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 9ddaa81af44ba1df971ae679a90d5c3a50d60f89..a5c21340759327e100da1da9528bb306aa5c7b67 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -1505,6 +1505,8 @@ HeapObjectContents HeapObject::ContentType() {
   } else if (type >= FIRST_FIXED_TYPED_ARRAY_TYPE &&
              type <= LAST_FIXED_TYPED_ARRAY_TYPE) {
     return HeapObjectContents::kMixedValues;
+  } else if (type == JS_ARRAY_BUFFER_TYPE) {
+    return HeapObjectContents::kMixedValues;
   } else if (type <= LAST_DATA_TYPE) {
     // TODO(jochen): Why do we claim that Code and Map contain only raw values?
     return HeapObjectContents::kRawValues;
@@ -6586,6 +6588,32 @@ void JSArrayBuffer::set_is_shared(bool value) {
 }
 
 
+// static
+template <typename StaticVisitor>
+void JSArrayBuffer::JSArrayBufferIterateBody(Heap* heap, HeapObject* obj) {
+  StaticVisitor::VisitPointers(
+      heap, obj,
+      HeapObject::RawField(obj, JSArrayBuffer::BodyDescriptor::kStartOffset),
+      HeapObject::RawField(obj,
+                           JSArrayBuffer::kByteLengthOffset + kPointerSize));
+  StaticVisitor::VisitPointers(
+      heap, obj, HeapObject::RawField(obj, JSArrayBuffer::kSize),
+      HeapObject::RawField(obj, JSArrayBuffer::kSizeWithInternalFields));
+}
+
+
+void JSArrayBuffer::JSArrayBufferIterateBody(HeapObject* obj,
+                                             ObjectVisitor* v) {
+  v->VisitPointers(
+      HeapObject::RawField(obj, JSArrayBuffer::BodyDescriptor::kStartOffset),
+      HeapObject::RawField(obj,
+                           JSArrayBuffer::kByteLengthOffset + kPointerSize));
+  v->VisitPointers(
+      HeapObject::RawField(obj, JSArrayBuffer::kSize),
+      HeapObject::RawField(obj, JSArrayBuffer::kSizeWithInternalFields));
+}
+
+
 Object* JSArrayBufferView::byte_offset() const {
   if (WasNeutered()) return Smi::FromInt(0);
   return Object::cast(READ_FIELD(this, kByteOffsetOffset));