Fix Number.prototype.toString with non-default radix wrt modulo.

test/mjsunit/number-tostring.js

 // Copyright 2008 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 133 matching lines @@
 assertEquals("8.8", (8.5).toString(16));
 assertEquals("-8.8", (-8.5).toString(16));
 
 assertEquals("1.1", (4/3).toString(3));
 assertEquals("11.1", (13/3).toString(3));
 assertEquals("0.01", (1/9).toString(3));
 assertEquals("10000", (81).toString(3));
 assertEquals("10000.01", (81 + 1/9).toString(3));
 assertEquals("0.0212010212010212010212010212010212", (2/7).toString(3));
 
+assertEquals("314404114120101444444424000000000000000",
+             (1.2345e+27).toString(5));
+
 // ----------------------------------------------------------------------
 // toFixed
 assertEquals("NaN", (NaN).toFixed(2));
 assertEquals("Infinity", (1/0).toFixed(2));
 assertEquals("-Infinity", (-1/0).toFixed(2));
 
 assertEquals("1.1111111111111111e+21", (1111111111111111111111).toFixed(8));
 assertEquals("0.1", (0.1).toFixed(1));
 assertEquals("0.10", (0.1).toFixed(2));
 assertEquals("0.100", (0.1).toFixed(3));
@@ skipping 171 matching lines @@
 assertEquals("-12", Number(-12.345).toPrecision(2));
 assertEquals("-1.2e+2", Number(-123.45).toPrecision(2));
 assertEquals("-1.2e+3", Number(-1234.5).toPrecision(2));
 assertEquals("-1.2e+4", Number(-12345).toPrecision(2));
 assertEquals("-1.235e+4", Number(-12345.67).toPrecision(4));
 assertEquals("-1.234e+4", Number(-12344.67).toPrecision(4));
 // Test that we round up even when the last digit generated is even.
 // dtoa does not do this in its original form.
 assertEquals("1.3", 1.25.toPrecision(2), "1.25.toPrecision(2)");
 assertEquals("1.4", 1.35.toPrecision(2), "1.35.toPrecision(2)");