The reason is when native_context_specialization flag is ture, X87 turbofan
  will hit the known issue that X87 will change a sNaN to qNaN by default. And
  then it will fail when bit-comparing the source (sNaN) and the result (qNaN).

BUG=

Review URL: https://codereview.chromium.org/1414733004

Cr-Commit-Position: refs/heads/master@{#31530}