Fix the failure introduced by 0381acf7 (r26213).

  When storing Double field to external double array, we need to do special
  qNaN --> sNan recovery on X87 port.

BUG=
R=weiliang.lin@intel.com

Review URL: https://codereview.chromium.org/879693006

Cr-Commit-Position: refs/heads/master@{#26477}