Keep prototype maps in dictionary mode until ICs see them

src/messages.cc

 // Copyright 2011 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.
 
 #include "src/messages.h"
 
 #include "src/api.h"
 #include "src/execution.h"
 #include "src/isolate-inl.h"
 #include "src/keys.h"
@@ skipping 265 matching lines @@
       }
     }
     if (CheckMethodName(isolate_, obj, name, fun_,
                         LookupIterator::PROTOTYPE_CHAIN_SKIP_INTERCEPTOR)) {
       return name;
     }
   }
 
   HandleScope outer_scope(isolate_);
   Handle<Object> result;
-  for (PrototypeIterator iter(isolate_, obj,
-                              PrototypeIterator::START_AT_RECEIVER);
-       !iter.IsAtEnd(); iter.Advance()) {
+  for (PrototypeIterator iter(isolate_, obj, kStartAtReceiver); !iter.IsAtEnd();
+       iter.Advance()) {
     Handle<Object> current = PrototypeIterator::GetCurrent(iter);
     if (!current->IsJSObject()) break;
     Handle<JSObject> current_obj = Handle<JSObject>::cast(current);
     if (current_obj->IsAccessCheckNeeded()) break;
     Handle<FixedArray> keys =
         KeyAccumulator::GetEnumPropertyKeys(isolate_, current_obj);
     for (int i = 0; i < keys->length(); i++) {
       HandleScope inner_scope(isolate_);
       if (!keys->get(i)->IsName()) continue;
       Handle<Name> name_key(Name::cast(keys->get(i)), isolate_);
@@ skipping 145 matching lines @@
       builder.AppendCharacter(*c);
     }
   }
 
   return builder.Finish();
 }
 
 
 }  // namespace internal
 }  // namespace v8