Revert of DevTools: Debugger StepInto/Out/Over initiated from a framework should not black-box it. (https://codereview.chromium.org/342713002/)

Reason for revert:
live-edit.html is failing in a batch of tests.

http://test-results.appspot.com/dashboards/flakiness_dashboard.html#group=%40ToT%20Blink&showLargeExpectations=true&showExpectations=true&tests=inspector%2Fsources%2Fdebugger%2Flive-edit.html

Original issue's description:
> DevTools: Debugger StepInto/Out/Over initiated from a framework should not black-box it.
> 
> BUG=267592
> R=yurys, pfeldman@chromium.org
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=177170

TBR=pfeldman@chromium.org,yurys@chromium.org,aandrey@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=267592

Review URL: https://codereview.chromium.org/360053002

git-svn-id: svn://svn.chromium.org/blink/trunk@177214 bbb929c8-8fbe-4397-9dbb-9b2b20218538