Revert of Throw when case mapping result > max string length (patchset #3 id:40001 of https://codereview.chromium.org/2236593002/ )

Reason for revert:
The test is very flaky and made it on many configurations into the top 10 of the slowest tests:

https://build.chromium.org/p/client.v8.ports/builders/V8%20Arm/builds/845
https://build.chromium.org/p/client.v8/builders/V8%20Win32%20-%20nosnap%20-%20shared/builds/15418
https://build.chromium.org/p/client.v8/builders/V8%20Linux/builds/12369/steps/Check/logs/durations

Original issue's description:
> Throw when case mapping result > max string length
>
> Throw 'Range Error: invalid string length' when the result of
> case mapping is longer than the max string length (kMaxLength in
> objects.h = 1 << 28 - 16).
>
> This is for case mapping with ICU.
>
> BUG=v8:5271
> TEST=intl/general/case-mapping.js with --icu_case_mapping
>
> Committed: https://crrev.com/c7a2046670468b900b9dbbb4ce45beb5e0e717fd
> Cr-Commit-Position: refs/heads/master@{#38565}

TBR=littledan@chromium.org,jshin@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5271

Review-Url: https://codereview.chromium.org/2236393002
Cr-Commit-Position: refs/heads/master@{#38582}