[runtime] Remove useless IN builtin.

src/runtime.js

 // Copyright 2006-2008 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.
 
 // This files contains runtime support implemented in JavaScript.
 
 // CAUTION: Some of the functions specified in this file are called
 // directly from compiled code. These are the functions with names in
 // ALL CAPS. The compiled code passes the first argument in 'this'.
 
@@ skipping 406 matching lines @@
   }
   throw %make_type_error(kStrongImplicitConversion);
 }
 
 
 /* -----------------------------
    - - -   H e l p e r s   - - -
    -----------------------------
 */
 
-// ECMA-262, section 11.8.7, page 54.
-function IN(x) {
-  if (!IS_SPEC_OBJECT(x)) {
-    throw %make_type_error(kInvalidInOperatorUse, this, x);
-  }
-  if (%_IsNonNegativeSmi(this)) {
-    if (IS_ARRAY(x) && %_HasFastPackedElements(x)) {
-      return this < x.length;
-    }
-    return %HasElement(x, this);
-  }
-  return %HasProperty(x, this);
-}
-
-
 function CALL_NON_FUNCTION() {
   var delegate = %GetFunctionDelegate(this);
   return %Apply(delegate, this, arguments, 0, %_ArgumentsLength());
 }
 
 
 function CALL_NON_FUNCTION_AS_CONSTRUCTOR() {
   var delegate = %GetConstructorDelegate(this);
   return %Apply(delegate, this, arguments, 0, %_ArgumentsLength());
 }
@@ skipping 367 matching lines @@
   "call_function_proxy_as_constructor_builtin", CALL_FUNCTION_PROXY_AS_CONSTRUCTOR,
   "call_function_proxy_builtin", CALL_FUNCTION_PROXY,
   "call_non_function_as_constructor_builtin", CALL_NON_FUNCTION_AS_CONSTRUCTOR,
   "call_non_function_builtin", CALL_NON_FUNCTION,
   "compare_builtin", COMPARE,
   "compare_strong_builtin", COMPARE_STRONG,
   "concat_iterable_to_array_builtin", CONCAT_ITERABLE_TO_ARRAY,
   "div_builtin", DIV,
   "div_strong_builtin", DIV_STRONG,
   "equals_builtin", EQUALS,
-  "in_builtin", IN,
   "mod_builtin", MOD,
   "mod_strong_builtin", MOD_STRONG,
   "mul_builtin", MUL,
   "mul_strong_builtin", MUL_STRONG,
   "reflect_apply_prepare_builtin", REFLECT_APPLY_PREPARE,
   "reflect_construct_prepare_builtin", REFLECT_CONSTRUCT_PREPARE,
   "sar_builtin", SAR,
   "sar_strong_builtin", SAR_STRONG,
   "shl_builtin", SHL,
   "shl_strong_builtin", SHL_STRONG,
@@ skipping 19 matching lines @@
 
 utils.Export(function(to) {
   to.ToBoolean = ToBoolean;
   to.ToLength = ToLength;
   to.ToNumber = ToNumber;
   to.ToPrimitive = ToPrimitive;
   to.ToString = ToString;
 });
 
 })