Avoid name clashes of builtins and runtime functions.

src/harmony-math.js

 // Copyright 2013 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.
 
 'use strict';
 
 // ES6 draft 09-27-13, section 20.2.2.28.
 function MathSign(x) {
   x = TO_NUMBER_INLINE(x);
   if (x > 0) return 1;
@@ skipping 114 matching lines @@
     var summand = n * n - compensation;
     var preliminary = sum + summand;
     compensation = (preliminary - sum) - summand;
     sum = preliminary;
   }
   return MathSqrt(sum) * max;
 }
 
 
 // ES6 draft 09-27-13, section 20.2.2.16.
-function MathFround(x) {
+function MathFroundJS(x) {
   return %MathFround(TO_NUMBER_INLINE(x));
 }
 
 
 function MathClz32(x) {
   x = ToUint32(TO_NUMBER_INLINE(x));
   if (x == 0) return 32;
   var result = 0;
   // Binary search.
   if ((x & 0xFFFF0000) === 0) { x <<= 16; result += 16; };
@@ skipping 81 matching lines @@
     "trunc", MathTrunc,
     "sinh", MathSinh,
     "cosh", MathCosh,
     "tanh", MathTanh,
     "asinh", MathAsinh,
     "acosh", MathAcosh,
     "atanh", MathAtanh,
     "log10", MathLog10,
     "log2", MathLog2,
     "hypot", MathHypot,
-    "fround", MathFround,
+    "fround", MathFroundJS,
     "clz32", MathClz32,
     "cbrt", MathCbrt,
     "log1p", MathLog1p,
     "expm1", MathExpm1
   ));
 }
 
 
 ExtendMath();