Fix store IC writability check in strict mode.

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 1342 matching lines @@
   if (FLAG_use_ic && !receiver->IsJSGlobalProxy()) {
     LookupResult lookup(isolate());
 
     if (LookupForWrite(receiver, name, &lookup)) {
       // Generate a stub for this store.
       UpdateCaches(&lookup, state, strict_mode, receiver, name, value);
     } else {
       // Strict mode doesn't allow setting non-existent global property
       // or an assignment to a read only property.
       if (strict_mode == kStrictMode) {
-        if (lookup.IsFound() && lookup.IsReadOnly()) {
+        if (lookup.IsProperty() && lookup.IsReadOnly()) {
           return TypeError("strict_read_only_property", object, name);
         } else if (IsContextual(object)) {
           return ReferenceError("not_defined", name);
         }
       }
     }
   }
 
   if (receiver->IsJSGlobalProxy()) {
     // TODO(ulan): find out why we patch this site even with --no-use-ic
@@ skipping 1189 matching lines @@
 #undef ADDR
 };
 
 
 Address IC::AddressFromUtilityId(IC::UtilityId id) {
   return IC_utilities[id];
 }
 
 
 } }  // namespace v8::internal