Optimistically assume that elements IC only transition once.

src/stub-cache.h

 // 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 151 matching lines @@
                                        StrictModeFlag strict_mode);
 
   // ---
 
   Handle<Code> ComputeKeyedStoreField(Handle<String> name,
                                       Handle<JSObject> receiver,
                                       int field_index,
                                       Handle<Map> transition,
                                       StrictModeFlag strict_mode);
 
-  Handle<Code> ComputeKeyedLoadOrStoreElement(Handle<JSObject> receiver,
+  Handle<Code> ComputeKeyedLoadOrStoreElement(Handle<Map> receiver_map,
                                               KeyedIC::StubKind stub_kind,
                                               StrictModeFlag strict_mode);
 
   // ---
 
   Handle<Code> ComputeCallField(int argc,
                                 Code::Kind,
                                 Code::ExtraICState extra_state,
                                 Handle<String> name,
                                 Handle<Object> object,
@@ skipping 711 matching lines @@
   Handle<JSFunction> constant_function_;
   bool is_simple_api_call_;
   Handle<FunctionTemplateInfo> expected_receiver_type_;
   Handle<CallHandlerInfo> api_call_info_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_STUB_CACHE_H_