Revert of DevTools: fix importScript function to set correct sourceURL (https://chromiumcodereview.appspot.com/134223004/)

Reason for revert:
New sourceURL does not respect path.

Original issue's description:
> DevTools: fix importScript function to set correct sourceURL
> 
> This patch uses window.location fields to generate correct sourceURL
> instead of parsing window.location.href manually.
> 
> BUG=337151
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=165636

TBR=lushnikov@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=337151

Review URL: https://codereview.chromium.org/145133014

git-svn-id: svn://svn.chromium.org/blink/trunk@165718 bbb929c8-8fbe-4397-9dbb-9b2b20218538