This reverts commit 9461fe24.

Reason for revert: Breaks a test in Node.js: 
 parallel/test-util-inspect

=== release test-util-inspect ===                                              
Path: parallel/test-util-inspect
#
# Fatal error in , line 0
# unreachable code
#

==== C stack trace ===============================


Original change's description:
> [builtins] don't inline calls for common Promise ops in async builtins
> 
> InternalResolvePromise, InternalPromiseReject and
> InternalPerformPromiseThen generate quite a lot of code.
> 
> This change adds 3 new TF stubs which inline calls to these builtins.
> These stubs are invoked rather than inlining those operations listed
> above directly. This is done for Async Iteration builtins, as well as
> Async Function builtins. Promise builtins are left as they were, and
> continue to inline these calls.
> 
> This results in a roughly 99kb reduction in snapshot_blob.bin on an x64
> release build.
> 
> BUG=v8:5855
> R=​gsathya@chromium.org, jgruber@chromium.org
> 
> Change-Id: I3349d0f0353a72270ae40b974312d64d1c8a9e46
> Reviewed-on: https://chromium-review.googlesource.com/461269
> Commit-Queue: Caitlin Potter <caitp@igalia.com>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Reviewed-by: Sathya Gunasekaran (ooo until April 10) <gsathya@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#44445}

TBR=mstarzinger@chromium.org,gsathya@chromium.org,caitp@igalia.com,jgruber@chromium.org,v8-reviews@googlegroups.com,bmeurer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5855

Change-Id: Iabcdf8b025cc9b053a858f8e74389638ac000ba0
Reviewed-on: https://chromium-review.googlesource.com/469946Reviewed-by: Franziska Hinkelmann <franzih@chromium.org>
Commit-Queue: Franziska Hinkelmann <franzih@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44448}