Revert of IDL compiler: sync Python to r165262 (https://codereview.chromium.org/138033017/)

Reason for revert:
Underlying Perl change reverted; sync Python
Perl revert in r165372
Revert of Add use counters for using Attrs as Nodes.
https://codereview.chromium.org/130703003/

Original issue's description:
> IDL compiler: sync Python to r165262
> 
> Python side to:
> Add use counters for using Attrs as Nodes.
> https://codereview.chromium.org/127723002
> 
> There are other cases (for interface Node itself), which I'll handle
> when finalizing Node.idl.
> 
> BUG=239771
> TBR=haraken
> NOTRY=true
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=165266

TBR=haraken@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=239771

Review URL: https://codereview.chromium.org/142593004

git-svn-id: svn://svn.chromium.org/blink/trunk@165373 bbb929c8-8fbe-4397-9dbb-9b2b20218538