This reverts commit 1e49864f.

Reason for revert: Crashing test on the waterfall https://logs.chromium.org/v/?s=chromium%2Fbb%2Fclient.v8%2FV8_Linux_gcc_4.8%2F16871%2F%2B%2Frecipes%2Fsteps%2FCheck%2F0%2Flogs%2FReturnMultipleRandom%2F0

Original change's description:
> [turbofan] Implement on-stack returns (Intel)
> 
> Add the ability to return (multiple) return values on the stack:
> 
> - Extend stack frames with a new buffer region for return slots.
>   This region is located at the end of a caller's frame such that
>   its slots can be indexed as caller frame slots in a callee
>   (located beyond its parameters) and assigned return values.
> - Adjust stack frame constructon and deconstruction accordingly.
> - Extend linkage computation to support register plus stack returns.
> - Reserve return slots in caller frame when respective calls occur.
> - Introduce and generate architecture instructions ('peek') for
>   reading back results from return slots in the caller.
> - Aggressive tests.
> - Some minor clean-up.
> 
> So far, only ia32 and x64 are implemented.
> 
> Change-Id: I9532ad13aa307c1dec40548c5b84600fe2f762ce
> Reviewed-on: https://chromium-review.googlesource.com/766371
> Commit-Queue: Andreas Haas <ahaas@chromium.org>
> Reviewed-by: Ben Titzer <titzer@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49994}

TBR=titzer@chromium.org,rossberg@chromium.org,ahaas@chromium.org

Change-Id: Ib257e92448942f8ef07d5ef246f9381f4784f014
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/819637Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50000}