Use weak cell to embed property cell in StoreGlobal.

src/code-stubs.h

Index: src/code-stubs.h
diff --git a/src/code-stubs.h b/src/code-stubs.h
index f8009a2697428b0241558a77015080b98000f1e0..2c9f1fb94d264c93044d0386dc097dcdbea7f10b 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -1084,7 +1084,7 @@ class StoreGlobalStub : public HandlerStub {
                       CheckGlobalBits::encode(check_global));
   }
 
-  static Handle<HeapObject> global_placeholder(Isolate* isolate) {
+  static Handle<HeapObject> property_cell_placeholder(Isolate* isolate) {
     return isolate->factory()->uninitialized_value();
   }
 
@@ -1094,11 +1094,13 @@ class StoreGlobalStub : public HandlerStub {
       Code::FindAndReplacePattern pattern;
       pattern.Add(isolate()->factory()->meta_map(),
                   Map::WeakCellForMap(Handle<Map>(global->map())));
-      pattern.Add(isolate()->factory()->global_property_cell_map(), cell);
+      pattern.Add(Handle<Map>(property_cell_placeholder(isolate())->map()),
+                  isolate()->factory()->NewWeakCell(cell));
       return CodeStub::GetCodeCopy(pattern);
     } else {
       Code::FindAndReplacePattern pattern;
-      pattern.Add(isolate()->factory()->global_property_cell_map(), cell);
+      pattern.Add(Handle<Map>(property_cell_placeholder(isolate())->map()),
+                  isolate()->factory()->NewWeakCell(cell));
       return CodeStub::GetCodeCopy(pattern);
     }
   }