Fix unwanted float-to-double-promotions

Fix unwanted float-to-double-promotions

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.

Committed: https://crrev.com/fde36818c60f5b7b1c80acbad4a99ade5556e3f5
Cr-Commit-Position: refs/heads/master@{#31125}

[skomski, 2015-10-06 13:19:36]

karl@skomski.com changed reviewers:
+ bmeurer@chromium.org

[skomski, 2015-10-06 13:21:45]

PTAL

[Benedikt Meurer, 2015-10-06 14:04:30]

lgtm

[skomski, 2015-10-06 14:19:37]

The CQ bit was checked by karl@skomski.com to run a CQ dry run

[commit-bot: I haz the power, 2015-10-06 14:19:46]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1372133006/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1372133006/1

[commit-bot: I haz the power, 2015-10-06 14:41:17]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-10-06 14:41:18]

Dry run: This issue passed the CQ dry run.

[skomski, 2015-10-06 14:48:51]

The CQ bit was checked by karl@skomski.com

[commit-bot: I haz the power, 2015-10-06 14:49:04]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1372133006/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1372133006/1

[commit-bot: I haz the power, 2015-10-06 14:50:36]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-06 14:50:50]

Patchset 1 (id:??) landed as
https://crrev.com/fde36818c60f5b7b1c80acbad4a99ade5556e3f5
Cr-Commit-Position: refs/heads/master@{#31125}