Ensure that the length property of bound functions are actual unique

src/runtime.h

 // 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 191 matching lines @@
   /* Numbers */ \
   F(NumberToRadixString, 2, 1) \
   F(NumberToFixed, 2, 1) \
   F(NumberToExponential, 2, 1) \
   F(NumberToPrecision, 2, 1)
 
 #define RUNTIME_FUNCTION_LIST_ALWAYS_2(F) \
   /* Reflection */ \
   F(FunctionSetInstanceClassName, 2, 1) \
   F(FunctionSetLength, 2, 1) \
+  F(BoundFunctionSetLength, 2, 1)    \
   F(FunctionSetPrototype, 2, 1) \
   F(FunctionSetReadOnlyPrototype, 1, 1) \
   F(FunctionGetName, 1, 1) \
   F(FunctionSetName, 2, 1) \
   F(FunctionSetBound, 1, 1) \
   F(FunctionRemovePrototype, 1, 1) \
   F(FunctionGetSourceCode, 1, 1) \
   F(FunctionGetScript, 1, 1) \
   F(FunctionGetScriptSourcePosition, 1, 1) \
   F(FunctionGetPositionForOffset, 2, 1) \
@@ skipping 429 matching lines @@
                                                 Handle<Script> script,
                                                 int position);
 
   // Helper functions used stubs.
   static void PerformGC(Object* result);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_RUNTIME_H_