Fix Math.log10 implementation for 1 - Number.EPSILON.

Fix Math.log10 implementation for 1 - Number.EPSILON.

R=svenpanne@chromium.org
BUG=v8:4025
LOG=N

Committed: https://crrev.com/2c01bd34b03cefe3946147aaf626f9e9938ee63e
Cr-Commit-Position: refs/heads/master@{#27815}

[Sven Panne, 2015-04-14 06:10:07]

The CQ bit was checked by svenpanne@chromium.org

[Sven Panne, 2015-04-14 06:10:08]

lgtm

[commit-bot: I haz the power, 2015-04-14 06:10:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1084853002/1

[commit-bot: I haz the power, 2015-04-14 06:20:12]

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

[commit-bot: I haz the power, 2015-04-14 06:20:13]

Try jobs failed on following builders:
  v8_linux_nodcheck_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_nodcheck_rel/build...)

[Yang, 2015-04-14 11:32:10]

The CQ bit was checked by yangguo@chromium.org

[Yang, 2015-04-14 11:32:11]

The patchset sent to the CQ was uploaded after l-g-t-m from
svenpanne@chromium.org
Link to the patchset: https://codereview.chromium.org/1084853002/#ps20001
(title: "preliminary fix for the test case")

[commit-bot: I haz the power, 2015-04-14 11:32:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1084853002/20001

[commit-bot: I haz the power, 2015-04-14 11:56:14]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-04-14 11:56:27]

Patchset 2 (id:??) landed as
https://crrev.com/2c01bd34b03cefe3946147aaf626f9e9938ee63e
Cr-Commit-Position: refs/heads/master@{#27815}