Unwanted promotions resulted into check_eq errors from this CR:
 https://codereview.chromium.org/1384873002/
 http://build.chromium.org/p/client.v8/builders/V8%20Arm/builds/3141/steps/Check/logs/4

Found via -Wdouble-promotion.

Review URL: https://codereview.chromium.org/1372133006

Cr-Commit-Position: refs/heads/master@{#31125}