Revert of [debugger] do not predict step in target for liveedit. (patchset #1 id:1 of https://codereview.chromium.org/1491743005/ )

Reason for revert:
[Sheriff] Layout test crashes:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/3220

Original issue's description:
> [debugger] do not predict step in target for liveedit.
>
> R=verwaest@chromium.org
>
> Committed: https://crrev.com/8f87ff5d62e996b07ffbde7e735daa603c1d7290
> Cr-Commit-Position: refs/heads/master@{#32553}

TBR=verwaest@chromium.org,yangguo@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1494143002

Cr-Commit-Position: refs/heads/master@{#32565}