[intrinsics] Drop the now obsolete %_DoubleHi and %_DoubleLo intrinsics.

test/mjsunit/asm/double-lo.js

-// Copyright 2015 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
-
-var stdlib = this;
-var foreign = {};
-var heap = new ArrayBuffer(64 * 1024);
-
-
-var m = (function(stdlib, foreign, heap) {
-  "use asm";
-  function lo1(i) {
-    i = +i;
-    return %_DoubleLo(i)|0;
-  }
-  function lo2(i, j) {
-    i = +i;
-    j = +j;
-    return %_DoubleLo(i)+%_DoubleLo(j)|0;
-  }
-  return { lo1: lo1, lo2: lo2 };
-})(stdlib, foreign, heap);
-
-assertEquals(0, m.lo1(0.0));
-assertEquals(0, m.lo1(-0.0));
-assertEquals(0, m.lo1(Infinity));
-assertEquals(0, m.lo1(-Infinity));
-assertEquals(0, m.lo2(0.0, 0.0));
-assertEquals(0, m.lo2(0.0, -0.0));
-assertEquals(0, m.lo2(-0.0, 0.0));
-assertEquals(0, m.lo2(-0.0, -0.0));
-for (var i = -2147483648; i < 2147483648; i += 3999773) {
-  assertEquals(%_DoubleLo(i), m.lo1(i));
-  assertEquals(i, m.lo1(%ConstructDouble(0, i)));
-  assertEquals(i, m.lo1(%ConstructDouble(i, i)));
-  assertEquals(i+i|0, m.lo2(%ConstructDouble(0, i), %ConstructDouble(0, i)));
-  assertEquals(i+i|0, m.lo2(%ConstructDouble(i, i), %ConstructDouble(i, i)));
-}