Fix a bug in delete for lookup slots.

src/runtime.h

 // Copyright 2010 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 266 matching lines @@
   F(Throw, 1, 1) \
   F(ReThrow, 1, 1) \
   F(ThrowReferenceError, 1, 1) \
   F(StackGuard, 0, 1) \
   F(PromoteScheduledException, 0, 1) \
   \
   /* Contexts */ \
   F(NewContext, 1, 1) \
   F(PushContext, 1, 1) \
   F(PushCatchContext, 1, 1) \
-  F(LookupContext, 2, 1) \
+  F(DeleteContextSlot, 2, 1) \
   F(LoadContextSlot, 2, 2) \
   F(LoadContextSlotNoReferenceError, 2, 2) \
   F(StoreContextSlot, 3, 1) \
   \
   /* Declarations and initialization */ \
   F(DeclareGlobals, 3, 1) \
   F(DeclareContextSlot, 4, 1) \
   F(InitializeVarGlobal, -1 /* 1 or 2 */, 1) \
   F(InitializeConstGlobal, 2, 1) \
   F(InitializeConstContextSlot, 3, 1) \
@@ skipping 252 matching lines @@
                                                 int position);
 
   // Helper functions used stubs.
   static void PerformGC(Object* result);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_RUNTIME_H_