Reason for revert:
[Sheriff] Breaks layout tests:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/3266
Please request rebase upstream first.
Original issue's description:
> Clean up promises and fix an edge case bug
>
> This patch builds on previous Promise spec compliance work by
> cleaning out some old code which existed to support
> Promise.prototype.chain, rephrasing some code to correspond more
> closely to the specification, and removing some incorrect brand
> checking. A test is added for a bug in an edge case which was fixed.
>
> R=rossberg
> BUG=v8:3641
> LOG=Y
>
> Committed: https://crrev.com/1deb89c8fd3cb69714ae0a24e3b5a4e78f6b73b4
> Cr-Commit-Position: refs/heads/master@{#32627}
TBR=rossberg@chromium.org,caitpotter88@gmail.com,littledan@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:3641
Review URL: https://codereview.chromium.org/1501763004
Cr-Commit-Position: refs/heads/master@{#32629}
0f2ed07f45