Revert of Fix compiler warnings on "make android_arm" (patchset #1 id:1 of https://codereview.chromium.org/2264283007/ )

Reason for revert:
Speculative revert because of roll blocker https://build.chromium.org/p/client.v8.ports/builders/V8%20Linux%20-%20arm64%20-%20sim%20-%20debug/builds/2241

Original issue's description:
> Fix compiler warnings on "make android_arm"
>
> Committed: https://crrev.com/3e809a6129d0097529c885579ac46e4acf4e99f6
> Cr-Commit-Position: refs/heads/master@{#38937}

TBR=bmeurer@chromium.org,jkummerow@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.

Review-Url: https://codereview.chromium.org/2286163002
Cr-Commit-Position: refs/heads/master@{#38961}