A64: Synchronize with r18084.

test/mjsunit/smi-mul-const.js

 // Copyright 2014 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 66 matching lines @@
 // 2^31 is a smi boundary on arm64 and x64.
 var two_31 = 2 * two_30;
 
 // TODO(rmcilroy): replace after r16361 with:  if (%IsValidSmi(two_31)) {
 if (true) {
   assertEquals(two_31, mul_by_neg_1(-two_31));
   assertUnoptimized(mul_by_neg_1);
 } else {
   assertEquals(two_30, mul_by_neg_1(-two_30));
   assertUnoptimized(mul_by_neg_1);
-}
+}