Don't use the keyed slow stub for named handlers.

src/ic/ic.cc

 // Copyright 2012 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/ic/ic.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/api-arguments.h"
 #include "src/arguments.h"
@@ skipping 1418 matching lines @@
     VectorStoreICStub stub(isolate, StoreICState(language_mode));
     return stub.GetCode();
   }
 
   return is_strict(language_mode)
              ? isolate->builtins()->StoreIC_Megamorphic_Strict()
              : isolate->builtins()->StoreIC_Megamorphic();
 }
 
 Handle<Code> StoreIC::slow_stub() const {
-  if (kind() == Code::STORE_IC) {
-    return isolate()->builtins()->StoreIC_Slow();
-  } else {
-    DCHECK(kind() == Code::KEYED_STORE_IC);
-    return isolate()->builtins()->KeyedStoreIC_Slow();
-  }
+  return isolate()->builtins()->StoreIC_Slow();
 }
 
 
 void StoreIC::UpdateCaches(LookupIterator* lookup, Handle<Object> value,
                            JSReceiver::StoreFromKeyed store_mode) {
   if (state() == UNINITIALIZED) {
     // This is the first time we execute this inline cache. Set the target to
     // the pre monomorphic stub to delay setting the monomorphic state.
     ConfigureVectorState(PREMONOMORPHIC);
     TRACE_IC("StoreIC", lookup->name());
@@ skipping 1283 matching lines @@
     KeyedLoadICNexus nexus(vector, vector_slot);
     KeyedLoadIC ic(IC::EXTRA_CALL_FRAME, isolate, &nexus);
     ic.UpdateState(receiver, key);
     ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, ic.Load(receiver, key));
   }
 
   return *result;
 }
 }  // namespace internal
 }  // namespace v8