The use of double variables to store bit patterns may lead to bit flips
when the stored bit pattern is a signaling NaN (sNaN). Operations on a
sNaN variable (even just returning the variable from a function) may
turn it into a quiet NaN (qNaN), flipping the signaling bit and
affecting the information stored in the variable.

We observed this behaviour on ia32 architectures and therefore in the
simulator builds for other platforms. The use of the wrapper class
Double should prevent this behaviour.

R=ahaas@chromium.org

Change-Id: Ibd1119924a59db771fd4c250689ad9c2a35fff75
Reviewed-on: https://chromium-review.googlesource.com/562771Reviewed-by: Jaideep Bajwa <bjaideep@ca.ibm.com>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Enrico Bacis <enricobacis@google.com>
Cr-Commit-Position: refs/heads/master@{#46533}