This reverts commit ec969ea3.

Reason for revert: test fails consistently on arm bots.
I can't repro the failure locally, but it does consume ~512MB of memory (for a single string, I think?), so my guess is that the bots don't have enough contiguous address space.

Original change's description:
> [builtins] Fix Array.p.join length overflow and invalid string length handling
> 
> - Fixes and simplify allocating the temporary fixed array for ToString-ed elements.
>   - When the array size is greater than representable by an intptr, it overflowed into a negative value causing a non-negative assert to fail.
>   - Simplify fallback behavior by always allocating a conservatively sized temporary fixed array. Previously, if the array had dictionary elements, the temporary fixed array was sized based on %GetNumberDictionaryNumberOfElements() and then resized when entering the fallback.
> 
> - Fixes related invalid string length handling. When the running total of the resulting string length overflowed or exceeded String::kMaxLength, a RangeError is thrown. Previously, this thrown RangeError bypassed JoinStackPop and left the receiver on the stack.
> 
> Bug: chromium:897404
> Change-Id: I157b71ef04ab06125a5b1c3454e5ed3713bdb591
> Reviewed-on: https://chromium-review.googlesource.com/c/1293070
> Commit-Queue: Peter Wong <peter.wm.wong@gmail.com>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#56907}

TBR=danno@chromium.org,peter.wm.wong@gmail.com,jgruber@chromium.org,tebbi@chromium.org

Change-Id: I8ca80bd75833aacc94ccb25ceb82bbc8880991db
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:897404
Reviewed-on: https://chromium-review.googlesource.com/c/1297471Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56915}