Revert "Support ES6 Map and Set in heap profiler"

src/heap-snapshot-generator.cc

Index: src/heap-snapshot-generator.cc
diff --git a/src/heap-snapshot-generator.cc b/src/heap-snapshot-generator.cc
index 6229386804b0361109178c73c482996dbd002d4e..f39ac1db2abe1720e5af6c71929516944ab5d302 100644
--- a/src/heap-snapshot-generator.cc
+++ b/src/heap-snapshot-generator.cc
@@ -1097,16 +1097,11 @@ bool V8HeapExplorer::ExtractReferencesPass1(int entry, HeapObject* obj) {
     ExtractJSGlobalProxyReferences(entry, JSGlobalProxy::cast(obj));
   } else if (obj->IsJSArrayBuffer()) {
     ExtractJSArrayBufferReferences(entry, JSArrayBuffer::cast(obj));
+  } else if (obj->IsJSWeakSet()) {
+    ExtractJSWeakCollectionReferences(entry, JSWeakSet::cast(obj));
+  } else if (obj->IsJSWeakMap()) {
+    ExtractJSWeakCollectionReferences(entry, JSWeakMap::cast(obj));
   } else if (obj->IsJSObject()) {
-    if (obj->IsJSWeakSet()) {
-      ExtractJSWeakCollectionReferences(entry, JSWeakSet::cast(obj));
-    } else if (obj->IsJSWeakMap()) {
-      ExtractJSWeakCollectionReferences(entry, JSWeakMap::cast(obj));
-    } else if (obj->IsJSSet()) {
-      ExtractJSCollectionReferences(entry, JSSet::cast(obj));
-    } else if (obj->IsJSMap()) {
-      ExtractJSCollectionReferences(entry, JSMap::cast(obj));
-    }
     ExtractJSObjectReferences(entry, JSObject::cast(obj));
   } else if (obj->IsString()) {
     ExtractStringReferences(entry, String::cast(obj));
@@ -1265,13 +1260,6 @@ void V8HeapExplorer::ExtractSymbolReferences(int entry, Symbol* symbol) {
 }
 
 
-void V8HeapExplorer::ExtractJSCollectionReferences(int entry,
-                                                   JSCollection* collection) {
-  SetInternalReference(collection, entry, "table", collection->table(),
-                       JSCollection::kTableOffset);
-}
-
-
 void V8HeapExplorer::ExtractJSWeakCollectionReferences(
     int entry, JSWeakCollection* collection) {
   MarkAsWeakContainer(collection->table());