Remove special handling of fields in combination with elements transitions in Crankshaft.

src/ic.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 215 matching lines @@
       index = map->IndexInCodeCache(name, handler);
       if (index >= 0) {
         map->RemoveFromCodeCache(String::cast(name), handler, index);
       }
     }
     return true;
   }
 
   // The stub is not in the cache. We've ruled out all other kinds of failure
   // except for proptotype chain changes, a deprecated map, a map that's
-  // different from the one that the stub expects, or a constant global property
-  // that will become mutable. Threat all those situations as prototype failures
-  // (stay monomorphic if possible).
+  // different from the one that the stub expects, elements kind changes, or a
+  // constant global property that will become mutable. Threat all those
+  // situations as prototype failures (stay monomorphic if possible).
 
   // If the IC is shared between multiple receivers (slow dictionary mode), then
   // the map cannot be deprecated and the stub invalidated.
   if (cache_holder == OWN_MAP) {
     Map* old_map = target->FindFirstMap();
     if (old_map == map) return true;
-    if (old_map != NULL && old_map->is_deprecated()) return true;
+    if (old_map != NULL) {
+      if (old_map->is_deprecated()) return true;
+      if (IsMoreGeneralElementsKindTransition(old_map->elements_kind(),
+                                              map->elements_kind())) {
+        return true;
+      }
+    }
   }
 
   if (receiver->IsGlobalObject()) {
     if (!name->IsName()) return false;
     Isolate* isolate = target->GetIsolate();
     LookupResult lookup(isolate);
     GlobalObject* global = GlobalObject::cast(receiver);
     global->LocalLookupRealNamedProperty(Name::cast(name), &lookup);
     if (!lookup.IsFound()) return false;
     PropertyCell* cell = global->GetPropertyCell(&lookup);
@@ skipping 2866 matching lines @@
 #undef ADDR
 };
 
 
 Address IC::AddressFromUtilityId(IC::UtilityId id) {
   return IC_utilities[id];
 }
 
 
 } }  // namespace v8::internal