Revert of Fix --max_old_space_size=4096 integer overflow.

Revert of Fix --max_old_space_size=4096 integer overflow. (patchset #1 id:1 of https://codereview.chromium.org/890563003/)

Reason for revert:
Win64 compile failure.

Original issue's description:
> Fix --max_old_space_size=4096 integer overflow.
>
> R=yangguo@chromium.org
>
> Committed: https://crrev.com/6253aa8908c55535473ddbe1db8e5a6f5e559b73
> Cr-Commit-Position: refs/heads/master@{#26371}

TBR=svenpanne@chromium.org,ben@strongloop.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/b856e8785933a2a9cd884ab8966fee0e7098927e
Cr-Commit-Position: refs/heads/master@{#26372}

[Yang, 2015-01-31 21:44:56]

Created Revert of Fix --max_old_space_size=4096 integer overflow.

[commit-bot: I haz the power, 2015-01-31 21:48:17]

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

[commit-bot: I haz the power, 2015-01-31 21:48:18]

Commit queue rejected this change because it did not recognize the base URL.
Please commit your change manually.

[commit-bot: I haz the power, 2015-02-01 08:09:03]

Patchset 1 (id:??) landed as
https://crrev.com/b856e8785933a2a9cd884ab8966fee0e7098927e
Cr-Commit-Position: refs/heads/master@{#26372}

[Yang, 2015-02-01 08:09:05]

Committed patchset #1 (id:1) manually as
b856e8785933a2a9cd884ab8966fee0e7098927e (tree was closed).