This reverts commit 521fa16e.

Reason for revert: fails tests under code-serializer:

https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20debug/builds/17691

Original change's description:
> [runtime] Slightly optimize creation of class literals.
> 
> TBR=bmeurer@chromium.org
> 
> Bug: v8:5799
> Change-Id: I61de5f8b3333db174dadf76ed983950acb39742b
> Reviewed-on: https://chromium-review.googlesource.com/649509
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49044}

TBR=rmcilroy@chromium.org,yangguo@chromium.org,mythria@chromium.org,gsathya@chromium.org,ishell@chromium.org,verwaest@chromium.org

Change-Id: I994edb855a8a0aa6e7e7476b0b013a46aac6f2e7
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:5799
Reviewed-on: https://chromium-review.googlesource.com/745581Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49046}