Ensure slow properties for simple {__proto__:null} literals.

src/factory.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_FACTORY_H_
 #define V8_FACTORY_H_
 
 #include "src/feedback-vector.h"
 #include "src/globals.h"
 #include "src/isolate.h"
@@ skipping 460 matching lines @@
 
   // Global objects are pretenured and initialized based on a constructor.
   Handle<JSGlobalObject> NewJSGlobalObject(Handle<JSFunction> constructor);
 
   // JS objects are pretenured when allocated by the bootstrapper and
   // runtime.
   Handle<JSObject> NewJSObjectFromMap(
       Handle<Map> map,
       PretenureFlag pretenure = NOT_TENURED,
       Handle<AllocationSite> allocation_site = Handle<AllocationSite>::null());
+  Handle<JSObject> NewSlowJSObjectFromMap(
+      Handle<Map> map,
+      int number_of_slow_properties = NameDictionary::kInitialCapacity,
+      PretenureFlag pretenure = NOT_TENURED);
 
   // JS arrays are pretenured when allocated by the parser.
 
   // Create a JSArray with a specified length and elements initialized
   // according to the specified mode.
   Handle<JSArray> NewJSArray(
       ElementsKind elements_kind, int length, int capacity,
       ArrayStorageAllocationMode mode = DONT_INITIALIZE_ARRAY_ELEMENTS,
       PretenureFlag pretenure = NOT_TENURED);
 
@@ skipping 271 matching lines @@
                                              Handle<Object> argument,
                                              int start_position,
                                              int end_position,
                                              Handle<Object> script,
                                              Handle<Object> stack_frames);
 
   Handle<DebugInfo> NewDebugInfo(Handle<SharedFunctionInfo> shared);
 
   // Return a map for given number of properties using the map cache in the
   // native context.
-  Handle<Map> ObjectLiteralMapFromCache(Handle<Context> context,
-                                        int number_of_properties,
-                                        bool* is_result_from_cache);
+  Handle<Map> ObjectLiteralMapFromCache(Handle<Context> native_context,
+                                        int number_of_properties);
 
   Handle<RegExpMatchInfo> NewRegExpMatchInfo();
 
   // Creates a new FixedArray that holds the data associated with the
   // atom regexp and stores it in the regexp.
   void SetRegExpAtomData(Handle<JSRegExp> regexp,
                          JSRegExp::Type type,
                          Handle<String> source,
                          JSRegExp::Flags flags,
                          Handle<Object> match_pattern);
@@ skipping 54 matching lines @@
   void SetStrictFunctionInstanceDescriptor(Handle<Map> map,
                                            FunctionMode function_mode);
 
   void SetClassFunctionInstanceDescriptor(Handle<Map> map);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_FACTORY_H_