This disables optimizations when using typed float arrays in
correctness fuzzer test cases. Otherwise, different NaN patterns
in float typed arrays might lead to different observations when
using the buffer in an int array view.

BUG=chromium:683579
NOTRY=true
TBR=Jarin, mvstanton, Igor Sheludko

Review-Url: https://codereview.chromium.org/2649923008
Cr-Commit-Position: refs/heads/master@{#42626}