Revert of DevTools: Split NetworkPanel.js (patchset #5 id:80001 of https://codereview.chromium.org/722683003/)

Reason for revert:
Don't overwrite files.

Original issue's description:
> DevTools: Split NetworkPanel.js
> 
> BUG=
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=185306

TBR=vsevik@chromium.org,apavlov@chromium.org,eustas@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/730463002

git-svn-id: svn://svn.chromium.org/blink/trunk@185358 bbb929c8-8fbe-4397-9dbb-9b2b20218538