Fix a potential crash in const declaration.

src/objects.cc

 // Copyright 2011 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 1865 matching lines @@
 
 
 void JSObject::LookupCallbackSetterInPrototypes(String* name,
                                                 LookupResult* result) {
   Heap* heap = GetHeap();
   for (Object* pt = GetPrototype();
        pt != heap->null_value();
        pt = pt->GetPrototype()) {
     JSObject::cast(pt)->LocalLookupRealNamedProperty(name, result);
     if (result->IsProperty()) {
-      if (result->IsReadOnly()) {
-        result->NotFound();
-        return;
-      }
-      if (result->type() == CALLBACKS) {
-        return;
-      }
+      if (result->type() == CALLBACKS && !result->IsReadOnly()) return;
+      // Found non-callback or read-only callback, stop looking.
+      break;
     }
   }
   result->NotFound();
 }
 
 
 MaybeObject* JSObject::SetElementWithCallbackSetterInPrototypes(
     uint32_t index,
     Object* value,
     bool* found,
@@ skipping 363 matching lines @@
       Execution::Call(trap, handler, ARRAY_SIZE(args), args, has_exception);
   if (has_exception) return NONE;
 
   // TODO(rossberg): convert result to PropertyAttributes
   USE(result);
   return NONE;
 }
 
 
 MaybeObject* JSObject::SetPropertyForResult(LookupResult* result,
-                                   String* name,
-                                   Object* value,
-                                   PropertyAttributes attributes,
-                                   StrictModeFlag strict_mode) {
+                                            String* name,
+                                            Object* value,
+                                            PropertyAttributes attributes,
+                                            StrictModeFlag strict_mode) {
   Heap* heap = GetHeap();
   // Make sure that the top context does not change when doing callbacks or
   // interceptor calls.
   AssertNoContextChange ncc;
 
   // Optimization for 2-byte strings often used as keys in a decompression
   // dictionary.  We make these short keys into symbols to avoid constantly
   // reallocating them.
   if (!name->IsSymbol() && name->length() <= 2) {
     Object* symbol_version;
@@ skipping 9401 matching lines @@
   if (break_point_objects()->IsUndefined()) return 0;
   // Single beak point.
   if (!break_point_objects()->IsFixedArray()) return 1;
   // Multiple break points.
   return FixedArray::cast(break_point_objects())->length();
 }
 #endif
 
 
 } }  // namespace v8::internal