This reverts commit c0e4e79b.

Reason for revert: Isolate tests fail. https://build.chromium.org/p/client.v8/builders/V8%20Linux/builds/20200/steps/Check%20-%20isolates/logs/stdio

Original change's description:
> [d8] implement setTimeout.
> 
> R=​ahaas@chromium.org, jarin@chromium.org
> 
> Bug: v8:6770
> Change-Id: Iebf4dc9f2dd75079c5362e02d859c48e2113cf20
> Reviewed-on: https://chromium-review.googlesource.com/643067
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Commit-Queue: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#47780}

TBR=yangguo@chromium.org,jarin@chromium.org,ahaas@chromium.org

Change-Id: I7abdedd7f5f4215d3df7b63f6656e78e1c4f9ea8
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:6770
Reviewed-on: https://chromium-review.googlesource.com/647592Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47781}