Reland v8::Private and related APIs

src/profiler/heap-snapshot-generator.cc

Index: src/profiler/heap-snapshot-generator.cc
diff --git a/src/profiler/heap-snapshot-generator.cc b/src/profiler/heap-snapshot-generator.cc
index 75de3d6d1ab02563c999a5a3e2c1473cd92d41f5..54173f5e2cfb4d312f13a656f04f475f93109614 100644
--- a/src/profiler/heap-snapshot-generator.cc
+++ b/src/profiler/heap-snapshot-generator.cc
@@ -836,7 +836,10 @@ HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object) {
                     HeapEntry::kString,
                     names_->GetName(String::cast(object)));
   } else if (object->IsSymbol()) {
-    return AddEntry(object, HeapEntry::kSymbol, "symbol");
+    if (Symbol::cast(object)->is_private())
+      return AddEntry(object, HeapEntry::kHidden, "private symbol");
+    else
+      return AddEntry(object, HeapEntry::kSymbol, "symbol");
   } else if (object->IsCode()) {
     return AddEntry(object, HeapEntry::kCode, "");
   } else if (object->IsSharedFunctionInfo()) {