[builtins] Migrate Number predicates and make them optimizable.

test/mjsunit/compiler/number-isinteger.js

+// Copyright 2016 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.
+
+// Flags: --allow-natives-syntax
+
+function test(f) {
+  assertTrue(f(0));
+  assertFalse(f(Number.MIN_VALUE));
+  assertTrue(f(Number.MAX_VALUE));
+  assertTrue(f(Number.MIN_SAFE_INTEGER));
+  assertTrue(f(Number.MIN_SAFE_INTEGER - 13));
+  assertTrue(f(Number.MAX_SAFE_INTEGER));
+  assertTrue(f(Number.MAX_SAFE_INTEGER + 23));
+  assertFalse(f(Number.NaN));
+  assertFalse(f(Number.POSITIVE_INFINITY));
+  assertFalse(f(Number.NEGATIVE_INFINITY));
+  assertFalse(f(1 / 0));
+  assertFalse(f(-1 / 0));
+  assertFalse(f(Number.EPSILON));
+}
+
+function f(x) {
+  return Number.isInteger(+x);
+}
+
+test(f);
+test(f);
+%OptimizeFunctionOnNextCall(f);
+test(f);