This reverts commit 98dec8f2.

Reason for revert: Speculative revert as win32/64 debug seems to
hang after this:
https://build.chromium.org/p/client.v8/builders/V8%20Win32%20-%20debug/builds/13691

Original change's description:
> [inspector] added Runtime.terminateExecution
> 
> Runtime.terminateExecution terminates current or next JavaScript
> call. Termination flag is automatically reset as soon as v8 call
> or microtasks are completed.
> 
> R=​pfeldman@chromium.org
> 
> Bug: chromium:820640
> Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
> Change-Id: Ie21c123be3a61fe25cf6e04c38a8b6c664622ed7
> Reviewed-on: https://chromium-review.googlesource.com/957386
> Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#51912}

TBR=dgozman@chromium.org,pfeldman@chromium.org,kozyatinskiy@chromium.org

Change-Id: I25258ca5e9a2c2c514f0834da0ef0f5e75421d52
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:820640
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Reviewed-on: https://chromium-review.googlesource.com/962002Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51914}